Giant Lump On Apollo's Face, Please Read And Reply ASAP

We often try hard to keep Apollo from going outside but many times everyone is careless and the cat lies in wait. So he goes outside often and comes back in. There are a few other cats in the neighborhood and I suspect (from hearing cat growls from outside) that she sometimes confronts them. However at other times, strangely enough he manages to coexist laying close to each under my Ford Explorer. He especially does this sometimes with a big blue female cat of the neighborhood.

Apollo, although male, is quite small for his gender. I sometimes wonder how he survives in the neighborhood especially with his tooth deformity. The big blue female is pretty......well.......big! Apollo would seem to be to small. His teeth deformity has made him have one saber tooth, so I wonder whether that is his chief weapon.

This morning he seemed fine but in the afternoon all of a sudden he had a GIANT Lump on his face. It is so big that I'm worried. I scheduled an appointment tomorrow with the vet but the lump is so big that I wonder whether it is something I should treat now.

First of all why does he have this giant lump? Could it be from fighting other cats (like the big blue female), snakebite (which I doubt) or some sort of disease? Or something else? I hope he doesn't have mumps or anything.

What do you think?

A sudden lump that large needs to be checked right away.
It is imperative that you keep the appointment with your vet tomorrow.

I would keep a close eye on him. If it was a poisonous snake or bug bite ... it could be life threating and he would need emergency care....now.
Let us know what you find out.

Is the lump hard or soft? Is it painful for Apollo when you touch it?

Most likely, it's an abscess caused by a bite from another cat. Keep your appointment for tomorrow, but as long as he's acting okay you don't need to take him to the hospital tonight. If it is an abscess, they will cut it open and drain it at the vet tomorrow (which will make him feel soooo much better) and send him home with antibiotics. He'll be just fine.