Here is the full list of all 25 Crush Your Enemies achievements.
Win the first battle in Generia.
Impale 3 of your enemies' heads.
Complete Brog The Barbarian's campaign.
Complete Fuzgut The Destroyer's campaign.
Collect your first beer.
Collect 50 pints of beer.
Collect 500 pints of beer.
Impale 20 of your enemies' heads.
Impale 50 of your enemies' heads.
Impale 123 of your enemies' heads.
Crush 1,000 Generian fighters.
Crush 10,000 Generian fighters.
Crush 20,000 Generian fighters.
Use the Dummy Barbarian 10 times.
Use the Shroom Moonshine 10 times.
Lose a battle.
Crush an enemy group using Warriors and Archers with Wizards to support them both.
Complete 3 objectives in 4 different battles in a row.
Kill 40 enemies at once with your Spiky Mine.
Win a multiplayer battle.
Win 10 multiplayer battles.
Play 100 multiplayer battles.
Lose multiplayer battles in 5 different locations.
Take over all the farms and survive until the enemy has no food left.
Collect 200 pints of beer.