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IGPX Immortal Grand Prix is an animated co-production by Production I.G. and Cartoon Network, acting as the first ever Toonami original anime series. The story follows teams competing in the IGPX, which is a mecha racing/battle circuit.
It exists in two iterations: the first as Toonami's 4th Total Immersion Event, a micro-series consisting of five 5-minute episodes; the second as a full-fledged series loosely related to the first, consisting of 26 episodes, which would air on Toonami.