Right now, Solaris was still occupying Jason's mana core, but Petri was already fully prepared to replace Solaris once the time was ripe.
By actively replenishing his mana, he was able to have a full mana core for the entire time, which made it much easier to initiate his plan that was rather simple.
The Cheetah of the Golden Sun was trying to extinguish the black flames that were scattered all over the ground.
They were spaced in a way that at least one of them occupied every square meter of space, however, that was easier said than done.
In the end, the Cheetah had to envelop the entire flame with its spatial affinity before transporting it to a faraway place where Jason could hardly reach it.
Other than that, the black flame could sustain itself as long as enough mana was around. It was just the flame's strength that would adjust according to the environment and Jason's will.
