AirMech Arena Achievement Guide & Road Map

AirMech Arena
AirMech Arena Achievement Guide

Overview:
Estimated achievement difficulty: 3/10
Offline: 0/30 (0/400)
Online: 30/30 (400/400)
Approximate amount of time to 400: 30-50 hours boosting if you pay for Gold VIP status in-game, 300+ without boosting if you pay for Gold VIP status in-game, 1000+ if you choose to not pay for Gold VIP status in-game.
Minimum number of playthroughs needed: N/A
Missable achievements: None
Does difficulty affect achievements?: No
Unobtainable/glitched achievements: None
Extra equipment needed?: None

Introduction:
AirMech Arena is a freemium real-time strategy mechanized combat game, using fixed bases that need to be captured to obtain resources and build units, with an ultimate goal of winning by destroying the main enemy fortress. It has micro-transactions built in that are generally focused on encouraging you to upgrade from free to Silver VIP or Gold VIP and/or purchasing diamonds (one of the two in-game currencies) so that you can obtain better gear and level up faster. The game has solo, co-op and peer-vs-peer scenarios (where you will spend most of your time). While the maximum level in the game is 100, the achievements only require that you advance to level 30. As with many strategy and freemium games, the the developers have designed the achievements such that you have quite a long grind ahead of you, even if you upgrade by spending money. The game is all server-side based, so if you are unable to connect to the AirMech Arena servers you will not be able to play any portion of the game (or even load the menus). Note also that the developers have changed various game mechanics since release and may do so again. Most notably, they made diamonds much harder to get and XP accumulate much slower than when the title was first released. Both of these changes have made the game take a significantly longer time to complete.

Abbreviated Walkthrough:
The first thing you should do is go to the Solo menu and complete the tutorial to unlock "Getting Started," and then (also found in the Solo menu) complete the challenges. While you will need to get three stars on each challenge to unlock "Challenger: 45 Stars," I recommend that you go through all of the challenges first without getting the best rating so you can unlock the last two challenges at the lowest possible experience level. The AI you fight on those two challenges have the same level that you do when you play them, so the higher level you are, the harder it will be to get 3 stars. Once you have 3 stars on the last two levels, go back and earn three stars on the other 13 challenges.

At this point, you should decide if you are going to aim for the 1000 hour grind or spend $5-10 to get an in-game boost. I strongly recommend the $10 gold VIP package, but it is possible to beat the game without spending any money. If the game had been released as a non-freemium arcade title, a $10-15 price point seems reasonable, and I do feel that the developers should be rewarded for their efforts just like I get paid for my work and you likely do for yours.

When you first start, you only have access to the Solo menu, so you will need to win either a skirmish or survival mission against the AI. Skirmish is much easier than survival, so I recommend that approach. The next step will be to unlock the PVP menu by winning a co-op game, which can be done with random teammates or AI bots on your team. Again, skirmish is much easier than survival, especially when you are a low level, so take that approach.

Once you have all of your game options unlocked, you will want to start leveling up and earning Kudos (in-game currency) and diamonds (if you purchased a VIP package) so that you can buy and use better equipment and mechs. Your ultimate goal is to be able to win 3 different survival games (solo, 2-player, and 4-player) before moving purely into the grind of leveling up. See the guide for "The Four Horsemen" for details.

Multiplayer:
Presuming you can dual-box or have a boosting partner, most of your time will be spent in PVP Custom Skirmish 1v1 matches. There is a requirement that you win a 3v3 PVP game in a certain way, but it can be done with five bots as the other players, and you will want to level up and have particular gear before you attempt it (see the guide for "Valedictorian" for full details). Most achievements will be unlocked here and can be easily boosted with a partner. If you need to play public matches they will take longer, but are all straightforward and obtainable.

Conclusion:
AirMech Arena is a well done RTS that most people will be able to pick up without much trouble. If you enjoyed the Halo Wars mechanic, this is very similar but without a story and nothing to do with Bungie. The one downside is that it has a frequent tendency to lag heavily even with geographically close players.

[XBA would like to thank Creech for this RoadMap]

Getting Started

10
Complete the Tutorial.
The tutorial is found in the Solo menu, and the first time you enter the game you will be prompted to play it. It should take no more than ten minutes and teach you the basics of creating and commanding units on the battlefield as well as how to maneuver your AirMech.
On a Roll

10
Win 3 consecutive online matches.
(3)
To be considered an online match by the game engine, the match must be in either the Coop or PvP menus. The easiest way to earn this achievement is to start a PvP Custom 1x1 match and have your opponent quit as soon as the map loads. To earn it without boosting you will need to beat random opponents three times in a row or win three survival matches in a row (or a combination of the two). If the game mode permits it, you can have AI on your team and it will still count for this achievement as long as your team wins. You can also play custom PVP against one or more AI and those games will count as well. If you are going to go against AI, you can set the AI difficulty to Trainee in the lobby to make it easier to win the match.
Win online Match

5
Be on the winning team in any match online!
To be considered an online match by the game engine, the match must be started from either the Coop or PvP menus. The easiest way to earn this achievement is to start a PvP Custom 1x1 match and have your opponent quit as soon as the map loads. To earn it without boosting you will need to beat random opponents three times in a row or win three survival matches in a row (or a combination of the two).

If the game mode permits it, you can have AI on your team and it will still count for this achievement as long as your team wins. You can also play custom PVP against one or more AI and that game would count for this achievement. If you are going to go against AI, you can set the AI difficulty to Trainee in the lobby to make it easier to win the match.
Win 10 online Matches

10
Win 10 Online Matches
(3)
To be considered an online match by the game engine, the match must be started from either the Coop or PvP menus. The easiest way to earn this achievement is to start a PvP Custom 1x1 match and have your opponent quit as soon as the map loads, and repeating this nine more times. To earn it without boosting you will need to beat a random opponent or win a survival match ten times.

If the game mode permits it, you can have AI on your team and it will still count for this achievement as long as your team wins. You can also play custom PVP against one or more AI and those games will count as well. If you are going to go against AI, you can set the AI difficulty to Trainee in the lobby to make it easier to win the match. These wins do not need to be consecutive.
Replicators Down!

10
Win a Match on any map without building anything.
(6)
Before attempting this achievement, from the main menu select Help & Options -> Gameplay and scroll down to the bottom. You will need to turn Auto Builder off (it should not have a check mark next to it).

The easiest approach is to then start a PvP Custom 1x1 match and have your opponent quit as soon as the map loads.

An alternate and much harder approach is to play a Coop survival or 2v2 or 3v3 skirmish match with random teammates and purely focus on using your AirMech as a killing machine. You will have to win without building any upgrades to your AirMech or any units at all.
Max Level

15
Reach Level 15 in any AirMech in an online or offline game.
While playing a match, you always start at level one and gain experience to level up as you and your units kill opposing units and capture bases. A yellow bar at the top of your screen indicates progress to the next level, with a maximum level of 15. Higher in-match levels are required to deploy certain units that are typically more powerful and expensive.

This achievement will absolutely unlock as you complete other achievements, but if you would like to focus on it early, play a Survival match. You will max out your level long before the last wave. You can also earn it in Skirmish or Custom matches simply by ensuring the game lasts long enough you and your units can do sufficient damage to level you up to 15.

Note that this in-match level is completely unrelated to the player level referred to in the "Moving on Up," "Going Pro," and "King of the Mountain" achievements.
Miser

10
Reach Level 10 in any AirMech in an online or offline game and win without spending any Ability points.
Before attempting this achievement, from the main menu select Help & Options -> Gameplay and scroll down to the bottom. You will need to turn Auto Builder off (it should not have a check mark next to it).

The ability menu is accessed in a match by holding . You will need to get to in-match level 10 and win the game without ever purchasing any of the items in the ability menu. You ARE permitted to purchase units, so this can be easily done with or without a partner in any game mode as long as you win. The easiest approach is with a partner in a PvP Custom 1x1 match where you build units and capture bases until you are level 10 and then either have your partner quit or destroy their fortress.
My hands are clean...

20
Win a match, online or offline, without destroying any Units with your AirMech. Let your units do the dirty work!
(1)
The easy approach on this is to start a PvP Custom 1x1 match and have your partner quit as soon as the map loads. However this achievement can be unlocked any game mode (excluding the tutorial and challenges) as long as you don't ever shoot with your AirMech. Focus on building and directing your units to capture one base at a time, or sneak some Assassin units in next to the enemy fortress and direct them to attack it by press to drop them.
Gladiator

20
Accumulate 100 Direct AirMech Kills online against human opponents.
(3)
You will need to kill 100 AirMechs that are piloted by humans (as opposed to AIs). This can be done in random matches, but as with most achievements in this game, the fastest approach is to start a PvP Custom 1x1 match against a partner and have them repeatedly leave their base and let you kill them. It will take longer to respawn as the game goes on so you may not want to boost this all in one game (especially given how many games you need to play for other achievements).

The kills will need to be by your AirMech, not your units, or they will not count toward this achievement. If boosting this, you also should ensure you complete the requirements for "Interceptor" when working on this achievement for maximum efficiency.
Damage Inc.

20
Do 1,000,000 damage with your AirMech.
All damage your AirMech does when shooting, whether against enemy units, AirMechs or fortresses counts toward this achievement. If you are actively involved in combat, especially capturing bases or playing Survival matches, you can reasonably do 20-40,000 damage in a match.

There is a tracker for this in the Stats screen available from the Play AirMech menu, about halfway down on the left side.
Moving on Up

10
Win an online match after reaching player level 10
Player levels are increased based on experience granted at the end of matches. Typically, you will earn more experience for longer matches, for winning and for having human players involved rather than AI. You will earn experience even when you lose as long as you don't quit out of the match. The winner of a match earns about 50% more base experience than the loser does. Your VIP status affects your experience level as well: Gold VIP increases experience earned toward player level by at least 15% and there are boosts available that can increase the experience earned by another 50-300%. Some of the boosts also increase the experience of everyone else in the match and can be stacked by multiple players. Finally, one of the pilots (Eric) will increase player level experience earned at the end of a match by an additional 5%. It is quite possible for a Gold VIP player to earn more experience when losing a match than a Silver VIP player (or non-VIP player) who wins.

Focus on unlocking all the other achievements first, other than the three level based achievements and the win X number of matches achievements. At that point, the fastest way to level up is to play PvP Custom 1x1 matches and have your opponent quit as soon as the map loads and you gain control of your mech. The person who quits will earn nothing, but you will earn 45-50 experience if you use Eric (or Ultimate Eric) as your pilot and have Gold VIP status (35-40 with Silver VIP). You can increase this if you have an XP booster as well. I unlocked an XP booster as the rare consumable that came with my Gold VIP and earned 70-75 experience per match using this method. With loading times, you can do two matches a minute using this method.

To unlock "Moving on Up" will take approximately 13,000 experience. There is no in-game tracker for how much experience you have earned at this time, or how far away from the next level you are. Once you reach level 10, you will then need to win one more match to unlock the achievement.
Going Pro

20
Win an online match after reaching player level 20
Player levels are increased based on experience granted at the end of matches. Typically, you will earn more experience for longer matches, for winning and for having human players involved rather than AI. You will earn experience even when you lose as long as you don't quit out of the match. The winner of a match earns about 50% more base experience than the loser does. Your VIP status affects your experience level as well: Gold VIP increases experience earned toward player level by at least 15% and there are boosts available that can increase the experience earned by another 50-300%.

Some of the boosts also increase the experience of everyone else in the match and can be stacked by multiple players. Finally, one of the pilots (Eric) will increase player level experience earned at the end of a match by an additional 5%. It is quite possible for a Gold VIP player to earn more experience when losing a match than a Silver VIP player (or non-VIP player) who wins.

Focus on unlocking all the other achievements first, other than the three level based achievements and the win X number of matches achievements. At that point, the fastest way to level up is to play PvP Custom 1x1 matches and have your opponent quit as soon as the map loads and you gain control of your mech. You will earn 45-50 experience if you use Eric (or Ultimate Eric) as your pilot and have Gold VIP status (35-40 with Silver VIP). You can increase this if you have an XP booster as well. I unlocked an XP booster as the rare consumable that came with my Gold VIP and earned 70-75 experience per match using this method. With loading times, you can do two matches a minute using this method.

To unlock "Going Pro" will take approximately 36,000 experience. There is no in-game tracker for how much experience you have earned at this time, or how far away from the next level you are. Once you reach level 20, you will then need to win one more match to unlock the achievement.
King of the Mountain

30
Win an online match after reaching player level 30
Player levels are increased based on experience granted at the end of matches. Typically, you will earn more experience for longer matches, for winning and for having human players involved rather than AI. You will earn experience even when you lose as long as you don't quit out of the match. The winner of a match earns about 50% more base experience than the loser does. Your VIP status affects your experience level as well: Gold VIP increases experience earned toward player level by at least 15% and there are boosts available that can increase the experience earned by another 50-300%.

Some of the boosts also increase the experience of everyone else in the match and can be stacked by multiple players. Finally, one of the pilots (Eric) will increase player level experience earned at the end of a match by an additional 5%. It is quite possible for a Gold VIP player to earn more experience when losing a match than a Silver VIP player (or non-VIP player) who wins.

Focus on unlocking all the other achievements first, other than the three level based achievements and the win X number of matches achievements. At that point, the fastest way to level up is to play PvP Custom 1x1 matches and have your opponent quit as soon as the map loads and you gain control of your mech. You will earn 45-50 experience if you use Eric (or Ultimate Eric) as your pilot and have Gold VIP status (35-40 with Silver VIP). You can increase this if you have an XP booster as well. I unlocked an XP booster as the rare consumable that came with my Gold VIP and earned 70-75 experience per match using this method. With loading times, you can do two matches a minute using this method.

To unlock "King of the Mountain" will take approximately 85,000 experience. There is no in-game tracker for how much experience you have earned at this time, or how far away from the next level you are. Once you reach level 30, you will then need to win one more match to unlock the achievement.
Sole Survivor

10
Win a solo survival match on any Survival map.
There are three maps to choose from when playing Survival, and this achievement will unlock whenever you survive the last wave on any map. The easiest map is entitled Survival, Spiral is moderate difficulty, and Last Stand is the hardest.

Using the easier map for this achievement, the basic winning strategy is the same regardless of the number of players. Prior to starting the match you will want ensure you are using the optimal equipment:
- AirMech - Warthog
- Pilot - Samson (Ultimate Samson is significantly better if you have diamonds to buy him with)
- Units - Moneymaker (for increased income), Honeypot (to repair turrets), T99 (to shoot enemies), Soldier (to capture bases).
The overall strategy you are going to undertake is to build a Honeypot in each socket around the fortress and surround it with T99s. For the four outlying bases, the creeps will capture them for more income and you can socket a Moneymaker in each one. You will want to speed up the process early, so you can build four soldiers at a time and carry them over to the base in question.

When the game starts, the first wave will come across the bridge to the northwest so build a Honeypot in that socket and one T99 that is placed in the middle of the roadway between the tree and the honeypot. Your base will take a very small amount of damage, but that one turret will destroy all of the first wave without further intervention. The Creeps will capture the eastern base on their own so you can build four soldiers at a time and carry them over to the other three bases. Once you have all four captured, build four Moneymakers and socket one at each base. This should match up nicely with the end of the first wave.

For the second wave, start another two T99s building and move your Honeypot and existing T99 to the Northeast bridge (socket the Honeypot). Put two more T99's on the bridge so you have a row of three turrets between the honeypot and the decorative (but indestructible) guard tower. Those three turrets will take care of wave two, so you can spend your time taking care of your overall defense layout. Build three more Honeypots and socket them around your fortress. Put three T99's blocking the road by each one (start with the southwest bridge since that is where wave 3 will come from) and then start destroying the fences around your fortress. They block the line of sight from your T99s and you will need them to be able to shoot in multiple directions in later waves.

Note that when placing a Honeypot, it shows a circle for the area of repair coverage. You will want to place at least two additional Honeypots on the southwest side of the base and two more on the northeast side of the base to fill in the gaps where the socketed Honeypots don't reach. At this point, you will want to build T99s until you run out of the ability to build anything, carpeting as much of the land as you can with T99s as long as they are placed within the coverage of a Honeypot. In particular, placing T99s on the lower dirt beneath the western and eastern socketed Honeypots will be critical for surviving from wave six on. When placing the unsocketed Honeypots, there are two bluffs that stick out directly to the north and south of the fortress that you can place Honeypots on that will provide coverage to the lower level. Ensure you put 4-5 T99s on the lower level to the north, south, east and west.

Whenever you run out of upkeep (the ability to place more units) upgrade your AirMech's abilities using the menu found by pressing . The critical upgrade you will absolutely need is the Gun Spray which enables you to shoot ground targets while flying. You can hover over a base or your fortress and shoot continuously until the base runs out of energy. This ability is why you need to have the Warthog as your AirMech. It is possible to win at Survival without using any abilities and earn the "Miser" achievement along the way, but it is much easier with this approach. If you are going to go without ability upgrades, switch your AirMech to a Striker so you can shoot continuously while on the ground. Remember that tanks take more damage if you shoot them from behind, so feel free to use your mobility to your advantage.

You may start losing bases after wave six, especially the northern base which gets assaulted with a huge amount of enemy infantry. Keep an eye out and if you have time you can fly infantry over to recapture or just ignore them if you are busy.

With this strategy you shouldn't take any damage to your fortress after wave one or two. The game will end after wave nine, unlocking the achievement.
Twin Survivors

10
Win a 2 player online survival match on any Survival map
(1)
See the guide for "Sole Survivor" for a complete breakdown of how to win at Survival.

With two players, if one has Ultimate Samson the other player should not build anything other than Soldiers to capture bases, ability upgrades, and Lockboxes (or Safeboxes) to transfer money to the player with Ultimate Samson. The units built by Ultimate Samson are much more powerful than those built by other pilots. When not transferring money, focus on killing enemy units and knocking down fences. If nobody has Ultimate Samson, then feel free to divide and conquer as long as everyone uses Samson as their pilot.
The Four Horsemen

20
Win a 4 player online survival match on any Survival map
(1)
See the guide for "Sole Survivor" for a complete breakdown of how to win at Survival.

With multiple players, if anyone has Ultimate Samson all other players should not build anything other than Soldiers to capture bases, ability upgrades, and Lockboxes (or Safeboxes) to transfer money to any player using Ultimate Samson. The units built by Ultimate Samson are much better than those built by other pilots. When not transferring money, focus on killing enemy units and knocking down fences. If nobody has Ultimate Samson, then feel free to divide and conquer as long as everyone uses Samson as their pilot.
Interceptor

15
Accumulate 20 human piloted enemy AirMech kills, each made while the enemy is carrying a unit.
(2)
You will need to kill 20 AirMechs that are piloted by humans (as opposed to AIs) while they are carrying at least one unit. This can be done in random matches, but as with most achievements in this game, the fastest approach is to start a PvP Custom 1v1 match against a partner and have them repeatedly build a unit, pick it up, leave their base and let you kill them. It will take longer to respawn as the game goes on so you may not want to boost this all in one game (especially given how many games you need to play for other achievements).

The kills will need to be by your AirMech, not your units, or they will not count toward this achievement. If boosting this, you will want to stack this with "Gladiator" for maximum efficiency.
Let's do this

5
Complete 10 matched games.
(1)
Any game that is not solo is considered a matched game. A completed game is one where you finish, win or lose. You simply cannot quit. You will need to win 500 or so to get up to level 30, so this will come without trying.
Match made in heaven

10
Win 20 matched games.
(2)
Any game that is not solo is considered a matched game. You will need to win 500 or so to get up to level 30, so this will come without trying.
Coming back for more!

10
Complete 100 matched games.
(1)
Any game that is not solo is considered a matched game. A completed game is one where you finish, win or lose. You simply cannot quit. You will need to win 500 or so to get up to level 30, so this will come without trying.
Serious Competitor

10
Win 200 matched games.
(2)
Any game that is not solo is considered a matched game. You will need to win 500 or so to get up to level 30, so this will come without trying.
Challenger: 10 Stars

5
Accumulate 10 Stars in the Challenges
There are 15 challenges found under the Solo menu that are intended to be an expanded tutorial. When completing the challenges you are awarded from 1-3 stars depending upon how long it takes you to complete the challenge.

Do the challenges before moving on to Co-op or PVP play, and initially I recommend you go through the challenges not worrying about how many stars you get until you get to challenge 14. You will fight an AI in challenges 14 and 15 where their level is equal to yours, so if you have leveled up to 30 before doing the challenges you will find them much harder than if you complete them early.

Bateboyback created a good walk-through for the challenges, which can be found here.
Challenger: 25 Stars

10
Accumulate 25 Stars in the Challenges
There are 15 challenges found under the Solo menu that are intended to be an expanded tutorial. When completing the challenges you are awarded from 1-3 stars depending upon how long it takes you to complete the challenge.

Do the challenges before moving on to Co-op or PVP play, and initially I recommend you go through the challenges not worrying about how many stars you get until you get to challenge 14. You will fight an AI in challenges 14 and 15 where their level is equal to yours, so if you have leveled up to 30 before doing the challenges you will find them much harder than if you complete them early.

Bateboyback created a good walk-through for the challenges, which can be found here.
Challenger: 45 Stars

20
Accumulate 45 Stars in the Challenges
(3)
There are 15 challenges found under the Solo menu that are intended to be an expanded tutorial. When completing the challenges you are awarded from 1-3 stars depending upon how long it takes you to complete the challenge.

Do the challenges before moving on to Co-op or PVP play, and initially I recommend you go through the challenges not worrying about how many stars you get until you get to challenge 14. You will fight an AI in challenges 14 and 15 where their level is equal to yours, so if you have leveled up to 30 before doing the challenges you will find them much harder than if you complete them early.

Bateboyback created a good walk-through for the challenges, which can be found here.
Valedictorian

10
Win in a 3v3 online game at least 3 levels above anyone else.
(1)
You will need to win a 3v3 PvP matchup where not only do you win, but your pilot's in-match level will need to finish at least three levels above anyone else. The maximum level in-match is 15, so this also means that you will need win relatively quickly because at some point you will stop leveling up.

While it can be boosted with 6 players in a custom match, it is quite obtainable with five AI bots in the game. When setting up the game, choose PvP Custom 3x3 and set the AI to Trainee. For your pilot use Eric or Ultimate Eric. During the safe period at the beginning of the game, hold and buy the XP boost. Throughout the game build armor and infantry, setting them to capture bases and actively help them out as that is the easiest way to level up in a match. Ideally you will want to win before you reach level 15 so that the AI doesn't have a chance to catch up to you.

Playing on a mid-sized map such as Chasm or Thar is your best chance of success. You need a map that is small enough for a quick win, but big enough to have room for the enemy AirMechs to have plenty to do instead of guarding their fortress.
Kicking Tires

15
Use each of the AirMech types at least once in game; online or offline.
There are nine types of AirMechs available. When you first start the game you get one free. The others have to be purchased using Kudos (one of the in-game currencies). After you purchase an AirMech, go play a game and ensure you equip it. You don't need to win, but you do need to finish the game. If boosting it, you can have your opponent quit from a PvP Custom 1x1 game as soon as the map loads and that will count toward this achievement.
Rock you like a Hurricane!

10
Win an online game where 100% of the enemy's base health is taken within 1 minute before being destroyed.
This achievement is intended to reward an overwhelming attack against an enemy fortress. All of the damage to the enemy fortress must be done in the 60 seconds prior to the game ending. If you have control of a base that is close to the enemy fortress and has a clear path, you can build up a collection of 10+ armor units, select them all by flying over them and holding , and then pressing to order them to assault the fortress. Feel free to jump in the trenches and help, of course.

By far the easier way is to start a PvP Custom 1x1 match with an opponent who is willing to quit out when the map loads as that will also unlock the achievement.
Boosted

10
Win a match, online or offline, using Boosters, all in Air mode.
(1)
Boosters are a unit type that you will need to purchase in the store prior to the game and then assign to an equipment slot. when the game starts, build them and pick them up. You will need to complete the entire game without ever transforming into the ground version of your mech and also will need to not get destroyed or run out of energy.

The easiest way to get this achievement is to start a PvP Custom 1x1 game, build and equip the Booster unit, and then have your opponent quit.
Blood Thirsty

30
Destroy 3 Human piloted AirMechs in the first 3 minutes of an online match.
(4)
You need to destroy three AirMechs that are piloted by humans - as opposed to AI - within the first three minutes of an online match. There are currently a lot of random players who are not very good, as is to be expected with a free game, so joining a PvP Unranked 3v3 match should give you plenty of targets. Focus on hunting down and killing AirMechs rather than units.

It can also be easily boosted in a PvP Custom 1x1 match with an opponent willing to let you kill them.

You do not need to win the match, but you do need to complete it. If you quit, the achievement will not unlock.
Can't stop eating!

10
Share 496 cakes.
(6)
This is designed as a social achievement, where you need to acquire something (in this case, cakes) and share them with others who are doing the same thing. Cakes are found in the shop under Cosmetics and can only be purchased with diamonds. When looking at the description, the item will need to include "+100% Yummy Cake" as an attribute. The item itself may be something else entirely, such as a turkey, but they all seem to be food-based. Prices vary, but currently the least expensive cake is 600 diamonds.

You can buy them from other players as well by going to the Player Market part of the shop. If you have a friend who has one or more to spare, they can sell them to you but note that the game does set a minimum price for every item so while it will be cheap compared to other items, it will not be free and it will require diamonds. When putting an item up for sale, one of the available fields lets the seller restrict the buyer to a single gamertag so that someone else doesn't purchase the item before you can buy it.

You can get 150 diamonds by completing the quest (found in the Play AirMech Arena -> Quests menu) for entering your email and agreeing to let Ubisoft email you about the game and promotions. You can opt out again after getting your diamonds if you do not want to actually get more spam by going to Main Menu -> Help & Options -> Contact and removing the check mark next to "Subscribe to Emails". You can also buy diamonds via the store and as a silver or gold VIP you can earn diamonds via quests.

Once you have at least one cake item, you will need to enter a lobby and equip it. If you change your mech, you will need to equip your cake items on every mech you use as they are considered cosmetic items that apply to the mech. However, you can equip one cake on every different mech you have, so it is just a matter of remembering to do so. Each mech has three different slots for "pets" (indicated by a grey bird when the slot is empty). While in a lobby, press repeatedly until you see a screen that has three grey birds, three grey spirals (used for flair items which are so rare at this point I am ignoring them, but technically it is possible to find cake items that go in flair spots), and a uniform color indicator. Select one of the pet slots and any cake items you own will show up in the inventory screen, allowing you to equip them.

So now you have at least one cake item equipped, so you can go play games and get credit toward this achievement by sharing it, right? Unfortunately, no. The only way to get credit is if someone else in the game also has at least one cake. They don't need to be on your team, which improves your odds, and you can see if anyone in a lobby has cake equipped before the game starts by pressing until the pet and flair screen appears. With one exception, the players who have cake also need to finish the game for the sharing to count. You will get credit for the total number of cakes in the lobby at the end of the game, whether or not they are on your team.

The one exception is if you are playing a 1v1 match, if your opponent (who must have at least one cake item) quits out, it ends the game and the code appears to consider this as both players with cake being in the game the whole time, so the winner will get incremented by the number of cakes they have equipped. The person who quit does not get any credit toward sharing cakes, and you don't get credit for the cakes they brought in, but it does make boosting via quitting games the fastest approach just as it is for ranking up.

You can view how many cakes you have shared in the Stats menu, near the bottom in the left column. Final note: While 496 cakes sounds like a lot, sharing three at a time (especially if both players have three cakes) makes this go by very fast. I had over 3,000 cakes shared by the time I hit level 30, which took a total of 548 games.