Kanye Kreed
A phrase coined by two young men in Northeast Ohio, which refers to the line "That that that that don't kill me can only make me stronger" in the Kanye West song "stronger". Followers of the kreed believe in just that, and whenever faced with a fearful or dangerous situation draw on the quote for strength and courage. 
When Brett was afraid to go on the very large rollarcoaster for fear he might die, Michael shouted "Kanye Kreed" and by doing so gave Brett the courage to ride it.