Here is the full list of all 71 Ignited Steel: Mech Tactics achievements.
Complete your first run
Buy a module in the store
Accept a contract in the store
Complete a contract
Reach the first boss
Reach the second boss
Defeat the first boss
Defeat the second boss
Defeat the final boss
Play 5 runs
Complete a fleeing level without attacking
Defeat 4 enemies with one attack
Keep the 3 mechs overheated at the same time during 3 turns
Kill the final boss with one of the mechs death explosion
Attract an enemy and then shoot tem with the shotgun
Defeat 50 enemies in one run
Reach the highest level of a pilot in one run
Reach the highest level of 3 pilots in one run
Complete three contracts in one run
Reach the final act without entering an store
Complete a run without losing any pilots
Defeat 100 enemies in total
Defeat 500 enemies in total
Spend 30000 credits buying modules in the store
Get 100000 credits in total
Complete 50 random events in total
Deal 30000 additional damage using heat
Cool 40000 heat points in total
Destroy 100 city buildings in total
Kill every type of enemy at least once
Unlock all module packs
Unlock all pilots
Unlock all modules
Unlock all achievements
Reach the Final Boss
Defeat the first boss without having lost any pilots in the run
Defeat the second boss without having lost any pilots in the run
Defeat 2 enemies with one attack
Defeat 3 enemies with one attack
Kill an enemy at full Health with 1 attack
Unlock 5 Pilots
Walk 500 tiles
Cool Down 100 times
Complete 25 contracts (multiple runs)
Kill 100 adjacent enemies
Kill 250 adjacent enemies
Overheat 250 enemies
Overheat your mechs 500 times
Complete the event chain of the mysterious investigator
Beat the game with Igret Soryu in your team
Beat the game with Sam Jehuty in your team
Beat the game with Aaliyah Kelly in your team
Beat the game with Hayase Salazar in your team
Beat the game with Liu Min Jun in your team
Beat the game with Marco Azanable in your team
Beat the game with Ada Amari in your team
Beat the game with Noah Bakker in your team
Beat the game with Silver Dingo in your team
Beat the game with Edi Asaju in your team
Beat the game with Isaac Inder in your team
Beat the game with Hidachi Kinkozu in your team
Beat New Game Plus with the "Crank The Heat Up!" modifier
Beat New Game Plus with the "Stingy Merchants" modifier
Beat New Game Plus with the "The Are Everywhere!" modifier
Beat New Game Plus with the "Updated Firewalls" modifier
Beat New Game Plus with the "Mechanics On Strike" modifier
Beat New Game Plus with at least 3 modifiers
Beat the game with Exa Falris in your team
Beat the game with F-OS V 0.1 in your team
Destroy 20 elite enemies
Achieve 15 victories in the altered gravity biomes