Wings & Block Duplication

All block duping will require moving with 0 speed. Keep in mind that even moving with a speed of 1 while trying to dupe will fail.

Vertical Dupe

Line up against the desired block to dupe and kick the shell upwards. By floating down with cape Mario for this dupe, it becomes a 2 frame window. There is no luck involved at all with a vertical dupe. The best example of vertical duping is Gnarly Wings.

Video: Gnarly - Cape (Wings, Quad Dupe) Source: Sten

Momentum Dupe

This dupe executes the exact same way as the vertical dupe, but aims to duplicate the block to the side. Shells and other objects, when grabbed, store the momentum they had when picked up (just like in the buzzy jump in Vanilla Dome 1). To dupe leftward, grab a shell with rightward momentum stored and vice versa to dupe rightward. Once again, floating down with a cape makes this dupe a 2 frame window, but this time there is a 50% chance to dupe vertically and a 50% chance to dupe diagonally. However, if the dupe is attempted one frame too late, it instead becomes a 50% chance to dupe horizontally and a 50% chance of hitting the block. The most common example of the momentum dupe is Forest of Illusion 1 wings.

Video: Forest of Illusion 1 Normal Exit - All Castles (Wings) Source: Sten

Horizontal Dupe

This dupe isn't used in regular speedruns, but is important nonetheless. First, stand in a 3 pixel window to the side of a block (not against it). If using cape Mario, float down and kick the shell upwards and if using small Mario, simply jump straight up then kick the shell up. This gives an 8 frame window for cape and a 4 frame window for small Mario. This gives a 50% chance of duping horizontally and a 50% chance of hitting the block. However, if Mario is one pixel too high, the block will dupe diagonally instead of horizontally.

Wall Dupe

This dupe is an offshoot of the horizontal dupe used for Vanilla Dome 1 wings. By attempting a horizontal dupe against a wall of blocks instead of against a single block, the 50% chance of hitting the block gets entirely mitigated, leaving only the 50% chance of horizontally duping the block. The frame window for the dupe also becomes much larger.

Video: Vanilla Dome 1 Normal Exit - Cape, Yoshi (Fast Wings) Source: Lui

Floor Dupe

This dupe is another offshoot of the horizontal dupe but isn't used in regular speedruns. If a block is one block above the ground, simply standing in the correct spot and kicking the shell upwards will work. Once again, this has a 50% chance of turning the block and a 50% chance of duping horizontally.

Magic Dupe

By manipulating the subpixel of a shell, the floor dupe can be attempted with more than a one block gap. This dupe is required for wings in Yoshi's Island 3 but nowhere else. Hit the red koopa out of his shell and grab his shell, then drop his shell on the ground and grab it after it stops moving 5 times. After doing this, stand in the right spot and kick the shell up. Once again, this will give a 50% chance of duping horizontally and 50% chance of hitting the block.