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