Not that I'm aware.
You'd have to all be in the same SG and use the SG rumble feature to do anything bigger than 8v8. The devs removed the ability to form teams before loading into the arena though, so you wouldn't be able to decide who goes on which team.
Yeah it's possible under the SG rumble setting, as Silit pointed out... But also since you can't pre-determine team placement, I think the only good use of it would be to maybe get some people's feet wet. As a medium of true arena PvP, it has lost some of it's value.
@TheKatalyst
My **** is bleeding.
Is there anyway to have 2 leagues battle each other in the arena? For example, if I have 12 villains and 12 heroes can I have the 2 teams form a league so they are on the same side, or do I have to make 4 teams that are all hostile to each other?
Thanks
"A true hero has the strength to stand against evil
without wavering where all others despair,
even if it means standing alone." - Kragothe Valour