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