Here is the full list of all 26 Deadly Rain achievements.
Kill 320 enemies in a single game.
Survive 20 rounds.
Unlock all areas.
Unlock the church.
Unlock the cabin.
Kill 240 enemies.
Kill 160 enemies in a single game.
Survive 10 rounds.
Unlock the mansion.
Kill 80 enemies in a single game.
Kill 60 enemies.
Use a healing syringe.
Kill an enemy with explosion.
Unlock the industrial area.
Survive 5 rounds.
Kill 30 enemies in a single game.
Kill 5 enemies in a single game.
Survive 1 round.
Kill 1 enemy.
Survive 30 rounds.
Survive 40 rounds.
Get all weapons.
Kill 960 enemies.
Kill 3840 enemies.
Kill 640 enemies in a single game.
Kill 1280 enemies in a single game.