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