this is my game btw, just testing it

Shadow Sonic: Appears in a 1 in 100 chance in the back room camera if NO ONE'S in it (including withered tails)

Shadow Mario: It's supposed to be a 1 in a 1,000,000 chance but I changed it to 1 in a 100. Appears if you put the monitor down.

Shadow Yoshi: 1 in a 100 chance to spawn in party room 3 if NO ONE'S in it.

Shadow Tails: Appears AUTOMATICALLY in the prize corner camera if The Memorial (Luiginette) escapes the music box. There's no chance for this, it's a guarantee.