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basically IDW (Instruction Down Warp) is a glitch that is caused by loading the instruction menu midgame which hides the player sprite (It's used to be belived the game warps you to the bottom of the screen, which wasn't true).
The speedrun mostly based on a different trick which is the reverse of IDW, Called IWW (Instruction Wrong Warp) that reactivates the player by stacking "Go!" buttons and restarting the game midgame which somehow doesn't reset the player but the game world it's self which allows you to respawn at the last checkpoint collected.
Made a new category for All Fish, the timing was incredibly off and wrong and the fact that All Fish is faster than Any% makes absolutely 0 sense so I changed the timing to normal.