i cant spawn costume mobs

i have looked up and there are no tutorials out there, this is prob a very unique problem i have. i have made a mod called SUS, since every amogus mod out there is dog**** i decided to make my own, but the problem is that most mobs cant even spawn, i tried spawning them with commands, using the spawn egg and they didnt spaw, i set the difficulty to hard and normal but it wont work, both the creatures and mobs wont spawn, no matter what, this problem came out of nowhere, i just edited 1 mob then all of a sudden like 80% of the mobs in the mod wont spawn, i can send file for further look but i need help, any explanations?