Here is the full list of all 23 Foreign Legion: Buckets of Blood achievements.
Kill 5 enemies with an air raid
Kill 1337 enemies in total
Reach level 20
Escort the bus safely without it taking damage
Kill all enemy waves in 7 minutes
Kill 2500 chickens
Play a game with only the Peace Badge and Bullets equipped
Kill 4 enemies with one rocket
Play a game with only the Smiley Badge equipped
Play a game with only the Night Vision Goggles equipped
Find the minigun
Purchase the Foreign Legion FAMAS
Make a kill chain of 10 kills
Repair the town hall 5 times in one round
Survive 30 minutes in endless mode
Beat the Village in the extreme difficulty
Finish the campaign on any difficulty
Destroy the supreme chicken overlord
Kill all chickens in one round
Make 15 headshots in one round
Win the game with all civilians alive
Kill 25 chickens
Purchase an outfit, helmet and accessory