User blog comment:JWarrior89/The Battle of the Criminally Insane: The Joker vs Professor Genki/@comment-4661256-20130124215456/@comment-4552610-20130130011627

The Penatrator is made of solid rubber and can still deal a good deal of damage. Imagine getting hit with a rubber mallet. It's going to do some serous damage. The Penatrator is able to stay relatively strait so their is likely some kind of strong support structure in the middle.

I'm pretty sure the Joker Venom just kills. The stuff he uses to take over people is an alteration of the original concoction and it won't be seen in this fight.

The TAR-21 won't have its assault rifle form. It's permanently a semi-automatic sniper rifle. Also, for a .50 caliber sniper rifle, it is doesn't do that much damage. Batman can take two hits from one before going down (at least in Arkham City, which is where we are taking its information from). The McMagnus, on the other hand, has been proven to kill nearly anything in one hit, save for the Genki, the Protagonist or a Brute.