On certain bosses, you beat them, the screen fades to black, but for a brief period of time the cut scene state ends and a game play state is temporarily initiated again. If you are mashing start during this, you will actually pause the game and confuse it, essentially soft locking you. This can happen on Monkey and Leopard.

Additionally, T'ai can make double jumps. Simply get hit in the air (monkeys are the easiest way to do this) and it will stun T'ai allowing you to jump a second time.

You may also be able to land on enemies heads for a jump.

You can also soft lock boar by phasing him as he jumps up / away

Death Warp: