Here is the full list of all 26 Obludia achievements.
Throw 50 dynamites.
Slay 30 Ghosts.
Use 10x Holy Cross.
Slay 20 Devils.
Find 20 chest.
Fire 100 Shotgun Shells
Slay 100 monsters with blade.
Complete the game.
Complete World 5 – Space Ship
Destroy 50 Alien eggs
Complete World 4 – Hell Gate
Save 10 princess.
Complete World 3 – Frozen Island
Find 1000 Coins.
Complete World 2 – Ancient Tower
Eat 20 Hamburger.
Slay 20 chickens.
Complete World 1 – Dungeon of Doom
Buy your first dog.
Find the legendary golden monkey statue
Slay your first enemy.
Die 50 times
Cast 50x Glacial Spike spell
Cast 50x Ring of Fire spell
Cast 50x Lightning Strike spell
Complete the game on HARD mode.