Open the Workshop door
Open the Garden door
Open the Castle door
Complete every level of the main campaign
Earn a gold medal in every level of the main campaign
Complete every bonus level
Earn a gold medal in every bonus level
Defeat Bomberbot
Earn a gold medal against Bomberbot
Defeat Bomberbot (hard)
Earn a gold medal against Bomberbot (hard)
Unlock all the Nitronomicon entries
Get a score of 10 or higher in a "Test of Speed" level
Detonate a total of 1000 bombs
Detonate a total of 150 color bombs
Make a chain of 10 consecutive explosions