Momentum

Momentum is a very core mechanic and is used in lots and lots of instances within the game. When Madeline jumps off of a zipper when it halts after a quick movement, she gets flung at a high speed. When she leaves a Dream Block, she retains some momentum. When she jumps off of the peak of a Cloud, she gets flung up. Momentum is used liberally within the vanilla game and in mods alike.