First off let me start by saying something I've said many times before: The more we can think outside of the "kill each other" box when it comes to competitive events in this game, the more fun events we'll actually see. I'm not sure who exactly has fun just going into a traditional arena and spamming the attack button at other people who are also spamming the attack button until something dies and then repeating this process for six hours a day for several years of their life, but... I suggest those people seek mental help and I suggest game developers stop encouraging them by even including that sort of PvP in their games to begin with.

So here's an idea for something that ISN'T that:

Hungry Hungry Roarmulus(usususes) would be an event in which a large dish-shaped arena features Roarmuli parked at the edges on different sides, one for each team. The game would actually be HALF "Hungry Hungry Hippos" and HALF Soccer/Football as the object is to PUSH monsters of some sort close enough to their team's Roarmulus that it can lean forward and take a great big bite. Of course, since the Roarmulus probably doesn't actually eat, and since the arena is run and spectated by monsters, we'd probably be using constructs of some sort.

Players would NOT be able to directly attack each other. Ever. If that was possible we'd see nothing but spawn camping and trapping each other in corners and that is NOT fun. The monsters, however, would probably be able to harm the players. Getting KO'd would of course only last a few seconds and then the players would be back on their feet automatically, though the standard team-mate reviving might be an option to get teammates back in the game quickly. Equipment would probably consist of arena-issued generic shields and armor, and the monsters themselves would be immune to damage of all sorts, but perhaps not other effects, so a player could use shock for it's slowing quality or make use of those new Haze bombs to make the monsters a little easier to round up. Naturally, anything you could do to them that somehow makes it easier or harder to herd them around is going to make it such for BOTH teams, so before you think of Graviton-ing them all into one big cluster and having your friend Troika-smash the whole group a lot closer to your goal, just remember someone on teh enemy team could run up and smack them into the opposite direction.

Oh, also the Roarmulus itself would occasionally flip out and try to kill everyone. Did I mention that? Maybe at certain intervals, or completely at random, or when you score points, or when you fail to feed it often enough. Maybe it would only hurt the opposing team's people. Or, to be really really cruel, maybe only it's OWN team. Or the monsters. Either way, it suddenly rising up with eyes all flashing should be a good indication that things are about to get really messy for SOMEONE.