I'm not sure I'm in the right spot for this or not, buuuuuut, I'm giving it a shot here.

My band has a session tomorrow and we're wanting to record some gang vocals (where everyone stands around a mic and yells at it for that group chant effect)

And I was wondering what type of mic is best for that. We've got a **** load to choose from in the studio, so anything you can think of we'll probably have access to.

Thanks in advance.
Basically any condenser.

In fact, basically any full stop. You won't be able to really tell the difference unless you have the hearing sensitivity of a wolf, or pic an obviously ill suited mic (for example drum mics.)
awesome, thanks guys. I'll have to check out what condensers we have in the mic cabinet.