Clearly not enough if the Avengers had to protect their planet.

[ It's a statement versus a dig, but unfortunately most things sound the same coming from Nebula. For better or worse. At the very least, of course Riordan Demigods couldn't protect from Avenger threats- because the Avengers were a fandom there. Oop. ]

Anything they could use. It can be used as a power source or to make stronger weapons.