From Tengen Toppa Gurren Lagann, Super Tengen Toppa Gurren Lagann is the largest and most powerful form of the titular mecha. STTGL is powered by Spiral Energy, which runs directly on the pilots' willpower (and given that the pilots are all incredibly determined, the amount of Spiral Energy in STTGL is immeasurable). The mecha is comprised of all the prior forms of Gurren Lagann, with Tengen Toppa Gurren Lagann at its head.
STTGL's main attack is the Giga Drill Breaker, which creates a drill at least ten times as large as the mecha from its right fist; when this drill collided with the Anti-Spiral's attack, it collapsed the dimension they were fighting in. It also presumably has access to everything its prior forms could do, including sword and rifle-based attacks powered by Spiral Energy. STTGL is impossibly large, apparently over a hundred times larger than its prior form, which is 10 million light years in height (roughly 100 times the size of the Milky Way Galaxy).
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