Set on Mars in the distant future, RoBoRumble frames its conflict as a contest to win a major arms contract: the victor earns the honor of defending Earth against aliens. This real-time 3D strategy game pairs two battle campaigns with multiplayer, while its defining idea is that players assemble their own fighting machines instead of choosing from a fixed roster of finished units.
Each Robo combines a chassis and a weapon, with an optional Booster adding another tactical choice. Chassis range from walkers and tracked vehicles to jet-propelled craft and teleporters; the arsenal spans conventional guns as well as devices that slow or fling opponents. Players begin with only a small selection of weapons and can expand it by assigning development contracts between missions. Meanwhile, a shared energy pool serves as both army base and construction budget: energy invested in a destroyed Robo returns to the pool, allowing replacement units to be built.
That mix of custom unit design and recyclable resources gives the campaign missions a different context from direct competition. The game describes two campaigns of 15 missions apiece, alongside multiplayer battles for up to four players over LAN or the internet.