Superman can fly what's that really prove....doesn't mean they can't be thrown into the sun or knocked through the Earth or anything. To bad Gokou's Kamehameha at that point couldn't destroy a planet so no he's not more durable than a planet. And so I guess Planet Destroying blasts > Solar System Destroying blast. If Cell's hype is so real then Gokou could have stopped the Planet Destroying blast. That's why it's pretty much given Cell can't do it since ssj2 Gokou > ssj2 Gohan from Cell Games. Also Majin Vegeta > ssj2 Gohan and he released all his energy at once and just created a large crater that didn't even nearly destroy a planet.
Using your words now you are saying that Vegeta SSJ 2 can not destroy a planet, when previously he show to Cell that he could, tell me why will Vegeta will explode to destroy the planet if what he wanted is to save the planet, and again, is not the size of the explosion. Is the power inside the explosion or blast, is not about Solar systems, or Galaxies, or planets, Cell was durable, resist the human army attack with tanks, planes, rockets, bazookas as nothing, before receive Piccolo´s, Tien´s Blast in his previous form without no damage, Goku disintegrate his head and part of his body, Cell regenerate, and Gohan disintegrate him completely, until his last cell, is the power in the blast that increase, DB is a whole one history from Goku meeting Bulma until going to train with Ubb, if you are going to say that they decrease in power or Goku and Roshi blast are the same, then you are not being objective. When Gohan blast vs Cell blast collide the whole planet shake, creating earthquakes. Saying that only create a crater is underestimate it, twisting the complete truth.
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