Complete a level having collected all of the secrets in that level
Complete a level faster than the allotted time
Complete a level having collected all of the pickups on that level
Complete the first level of the game
Pick up your first secret
Beat the speed run time on all levels
Complete the game having found all pickups and secrets, and completed every speed run
Complete a level after having picked up at least half of all the secrets in the game
Pick up all the secrets in the game and complete the level you're on
Get to the second world of the game
Get to the third world of the game
Get to Mustacho's lair and defeat him