Here is the full list of all 23 Frontline Tactics achievements.
Kill multiple enemies in a single burst.
Grenade fragments makes enemies bleed.
Pepper more than one target with bullets.
Blind and stun enemies.
Use cover and survive longer.
Defeat enemy elite troops.
Knowledge is power!
Dual wield-r-us.
Kill! Kill! Kill!
Win some missions to get feet wet.
Swiftly defeat the enemy.
First successful mission turn boys to men.
Win a lot of missions.
Unlock a little of everything.
Crossfire is good. More is better!
Unlock everything.
Defeat enemies of flesh and bone.
Grow your squad.
Deploy and extract a full team.
Perform slice and dice kills.
More skills are better than few.
Horde a lot of credits.
Buying credits is totally OK!