oh my $#@% god

[Carl the Llama]

hmm i just go tthat item i should look that up

You can only do it on Disk 3 as once you enter Midigar you cannot leave and the materia is in Midigar.

W-item Trick Tutorial - YouTube

no you can do it anywhere

Obviously you misunderstood this: The W-Item Materia can only be acquired once you enter Midigar at the end of Disk 2 (once you leave Midigar you will be on Disk 3), so the W-Item trick of duplicating loads of Sylkis Greens to feed the Chocobo's can only be used on Disk 3.