Get through The Graveyard

Get through The Catacombs

Defeat the Ghost King

Defeat the Ghost King three times

Defeat four enemies at the same time

Find a secret level

Destroy the Moai in the Snow Cliffs

Get to The Depths

Unlock every alternate skin

Unlock all nine original characters

Unlock the three newest characters

Defeat the Ghost King as the Ghost King

Score 100 or more points in a game

Beat the game with GhOsTY (only active in January)

Beat the game in Tourism Mode

Play Endless Mode. It does end.

Get a score of 40 or more in an Endless game