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From Unmariowiki

Subcon is a place in mario's dreams. He went there one night while singing the I can't Wait, To Be King! song. While in there, he noticed that his farts could create obstacles for Shy Guy's to bump into. Mario gained this power, until he met Wart, the ultimate evil. Mario called him a @#%#$%@#$%#$% and whooped his ^$%^#$%^ ***.