Here is the full list of all 24 The Light Brigade achievements.
Finish your first run, start to finish.
Defeat the Father.
Defeat the second boss.
Hold onto 1,000 coins at once during a run.
Use the wishing well.
Spend 1,000 gold at a store.
Kill an enemy sniper from far away.
Defeat the first boss.
Rescue an ally Light Brigade soldier out on a run.
Land 250 headshots. (accumulated)
Land 250 gunshots. (accumulated)
Reload 100 times. (accumulated)
Travel 1,000 meters. (accumulated)
Try to fire your weapon without first reloading it.
Use an enemy's dropped weapon to kill another enemy.
After death, find your ghost and pray to it.
Die and be revived for the first time.
Cock an ally Light Brigade soldier's rifle.
Pray to the Mother.
Never miss a shot during a fully completed run.
Every single shot during a fully completed run is a headshot.
Kill an enemy bomber using a grenade.
Kill an enemy priest using magic.
Have a hypnotized enemy kill another enemy.