I have heard a couple of times that there is a very simple way to spawn mushroom cows without spawn eggs and without a mushroom biome. Does anyone know how?
only way i've found a mooshroom is on my map that was created pre-tu7 is there was a biome shift and a mushroom biome added in. I found one by accident, (it wasn't a fully fledged one, it was just code shifted for animal spawning, had the same terrain it did previously) and there were 2 mooshrooms in it. I managed to lead them back to my town, and breed em.
Mushroom Cows