Sinister 10

Joker
Riddler
Two-Face
Penguin
Scarecrow
Bane (no venom)
Killer Croc
Mr. Freeze
Clayface (Karlo)
Man-Bat

Sinister 7

Kraven the Hunter
Mysterio
Vulture
Shocker
Chameleon
Boomerang
Kingpin

Batman's villains accidentally open an alternate dimension and wander into the Marvel universe. Joker leads the group and decides to take over the New York mob scene. Kingpin doesn't like the sound of that and creates his own team to take on Batman's rogues.

Fight takes place in an abandoned warehouse.

Round 1: Prep time

Round 2: No prep

Who wins?