Vagrant Lustoid 2

Speed does increase with power. Until you hit the border between sub-light and light-speed. None of those show that speed beyond light-speed is possible. And no, the death-beam one is not proof, because your eyes can theoretically adapt to speeds up to just below light speed, and that's what the beam was, until you can provide conclusive and substantive evidence that the beam was moving beyond light speed. But eyes cannot adapt to see at speeds beyond light speed. You'd get time lag, and Goku would have been killed by the beams.

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