Play Pong With Mario's Head!

Want to know how it's done?

In short: I manipulate where the moving objects (sprites) are located or where they despawn, then I swap the item in Yoshi's mouth with a flying ?-block (thus the yellow glitched shell) and using a glitch (stunning) to spawn a sprite which isn't used by SMW and since it tries to jump to the sprite routine location, it indexes everything wrong and jumps to a place I manipulated earlier with the sprites (OAM) and because of the P-Switch it jumps to controller registers and from there the arbitrary code execution is started.