The Ultimate Arena

[Xvito]

Me vs. You.
Yes, YOU!

 

[curlycrouton]

If anyone says Gordon Freeman vs. Master Chief......

Anyway, I'd have to say Prince Arthas vs. the Undead Version Of Himself.

 

[RetiarySword]

Gordon Freeman vs. Master Chief

 

[mokes310]

Anne Frank vs Lizzy Borden!

EDIT:

Chopper vs Neville Bartos

 

[shadow_pirate22]

Sauron (in his knight-esq form) vs. Umaril the Unfeatherd.
Sephiroth vs. The Emperor (Lost Kingdoms 2 emperor, not palpatine)
Grey Fox vs. Ryu Hayabusa

Paris Hilton vs The Predator.

as the halftime show.
And finally, a hunting match: Master Chief, Jim Raynor, and Samus Aran hunting Jack Thompson.

 

[wewontdie11]

The Jonas Brothers vs Satan, his minions and all his instruments or torture and pain.

 

[Leeathal]

The whole cast of power rangers versus a 60000000ft giant sandwitch

 

[zacaron]

Baraq Obama and George Bush. Bush will use too much power and Baraq will outsmart him.

it would not be very much of a fight

Spoiler

 

[Symp4thy]

Optimus Prime Vs. The Power Rangers Megazord

I'm gonna change that to Megazord vs. Voltron.