Name Battleship Arena Something Else?

[porkbob]

Challenges already exist in the game. So does arena. So it's very confusing to refer to the new battleship content as both arena and challenges in different screens!

Now, English is a pretty robust language, so surely there are some other words out there. I would kindly ask to find some other name to call this feature, to make it distinct. And please keep it consistent between the screens for the sake of sanity.  

One particular term I quite like is onslaught. It kind of makes sense, as you are fighting a military, to consider them waves of an onslaught. Although another one that could be up for grabs is gauntlet. (Maybe you can use that one for beasts in the future, though?)

Thanks for your consideration.