Location: open wastelands of Fury Road.
Bullet town has been cut off from resupplying the Citadel with bullets. Gas Town is also not in play.
The Haradrim have come for the water and food, and with their tower Olyphants, they have the best chance of scaling the walls .
So.... one big battle. The War Boys, with the War Rig, vs. all of the movie Mumakil with Haradrim warriors.
(For those who love their trivia, that was 20 armored Mumakil at the Battle of the Pelennor Fields in the movie.)