A cool battle of sorts happened in an anime called No Game No Life that seems like it could be a fun and unique arena battle on this forum where the characters must outsmart the other to win rather than just running up blindly swinging at each other. I'll copy and paste the rules to the battle to offer as good of an explanation as any:

[hider=Rules]
Similar to the normal Shiritori rules, each player takes turn to say a noun. The last character of the previous word said must be the first character of the next word to be said. Things that are present will disappear, and things that are not present will materialize. Players cannot cause the direct death of each other by stating vital components of the body. The noun stated must be a non-imaginary word. Sora noted that words which are non-imaginary but the opponent does not know of can also be used. 

The conditions for losing are:
1.Using a word that has already been said 
2.Being unable to answer within 30 seconds 
3.Being unable to continue 

In addition, when a word is stated, the effect is based on the meaning intended by the player who stated it. 
[/hider]

That being said, while the characters are fighting they can materialize or take away things from the arena based on what they say. If you are out of a weapon and they say "snakes", that word ends in the letter s so you could say "sword" to materialize a sword in your hand to help combat all the summoned snakes or whatever. Nothing you summon is technically on your side, so you can't summon a huge monster and expect it to fight for you. That being said you have to be careful what you summon or it could backfire. Also, although the rules don't say it here, you could still say stuff like oxygen or carbon because it won't eliminate all oxygen or carbon, just the oxygen or carbon outside of the player's body so it doesn't count as a direct death. 

So yes, you can summon nuclear bombs and such but those would blow up you as well so you have to be careful. In the anime you just had to outlive the other, even by a nanosecond to win, but in this case our characters will actually die for real and they can't be suicidal enough where they'd just kill everyone and call it a day. Also, for those who worry about destroying everything in the world, the battle is transported to an alternate dimension where the combatants are the only living things on the planet. All summoned things don't actually have a consciousness.

Anyone interested?