Here is the full list of all 33 Monster Boy and the Cursed Kingdom trophies - there are 18 bronze, 8 silver, 6 gold and 1 platinum.
Get every Trophy.
Defeat Xaros and save the kingdom from darkness.
Visit every corner of Monster World Kingdom.
Have Foximus forge every piece of Golden gear.
Open every chest in Monster World Kingdom.
Collect every Life Heart.
Restore all your forms after losing them.
Find the sacred orb that restores your original form.
Bring Nabu back to normal.
Return all three of the old heroes' items to the sanctuary.
Collect every Super Thunder Truffle.
Help Ollie find all of his lost music sheets.
Collect every Super Bomb Truffle.
Collect every Super Tornado Truffle.
Collect every Super Boomerang Truffle.
Make it to the end of the secret Cyber Dungeon.
Find the sacred orb that holds the power of Dragon form.
Upgrade a full set at a blacksmith.
Collect every Super Fire Truffle.
Ring the sanctuary bell.
Run a long distance without stopping in Lion form.
Find the sacred orb that holds the power of Lion form.
Swallow 10 mosquitos in Frog form.
Kill an enemy with a bomb you swallowed while in Frog form.
Defeat Malino the first time he challenges you to a race.
Upgrade your first item at a blacksmith.
Buy something from Zeke's shop.
Find the sacred orb that holds the power of Frog form.
Find the sacred orb that holds the power of Snake form.
Find your first Life Heart.
Sniff 10 secrets in Pig form.
Help free the legendary Pepelogoo.
Find your first coin fountain.