This glitch allows the player to get out-of-bounds in the Wooded Kingdom sub-area, Flooding Pipeway. To do this, perform a groundpound the moment the water level lowers to the point of Marios head, you may need to press jump right before performing your groundpound. Discovered by Veal of Maya

Fast strat for the 2nd sheep in Wooded

Stand in the gap in the flowers (or at a similar distance pre-peace), throw it to edge of falling platform, lower platform, then pick up rock before it hits the ground (do this by throwing your cap away from the rock or have y/x held from when you threw the rock)

Try to get the cap as far off the ledge as possible