Halo 3 has some pretty amazing customizable multiplayer features. My favorite by far has been this incredible pirate battle in the desert. Basically, your ships act as bases that the other team has to take over. Everyone is only equipped with a sword and a pistol, and being on the sand zaps away your shielding (so it really helps to have vehicles).
Here is a tale woven by me via the game’s theater feature.
Opposition starts flocking toward our ship
Their ship fast approaches ours
They waste no time unleashing their horde
I dispatch the first boarder ruthlessly
While Jimmy sneaks aboard their vessel
The last of their marauders is taken out