Marisa is slightly slower than lightspeed. If she was much slower, she wouldn't be able to fire the second attack before the first hit.
Well the scans are there for people to interpret. Marisa is talking about lightspeed before showing off an light based attack that is acknowledged by her opponent to be a light based attack. I feel that reasonably implies that the attack really is moving at lightspeed even if there isn't an explicit statement from a impartial source to clock in the true speed of the attack.
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SuperNiceDog was not so nice to my bracket.
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