Super Power/Mutation: Dragon of Heaven powers, or in other words the same powers as Kamui Shirou. Basically he keeps all of the esper and telepathy stuff, but loses the ability to hear wishes. And his unnatural tolerance for pain. And the teleporting. He gains the ability to make a kekkai - a spiritual barrier - but he won't be able to summon it. Nothing about his personality will be changed by it though.
Restrictions: Same as Kamui's. Retains his speed and strength, but the more he uses the ESP-ish powers, the more tired he gets. Large attacks tire him out faster. And Fuuma won't be able to summon the kekkai since that stems from a desire to protect people. Plus Kamui can't do it yet either, so Fuuma doesn't get to feel awesome for once.
Reasoning: Fuuma was basically born to be on the opposite side of the battle for the end of the world. Whatever side Kamui chose to be on, Fuuma would end up fighting against him. He did have the potential to become a Dragon of Heave if Kamui had chosen to be a Dragon of Earth. Kamui just didn't chose that, so I thought switching it for a day might be fun.
Any last questions? Hopefully this is okay? I talked to Kamui's mun, Killiana, and we thought a power swap for the day would be interesting, so... y/n/lobster? :D?