Multiverse: Deathstroke - Chapter 485: Black Hand

... e Wall. Only Kyle Rayner, the White Lantern, had ventured there and returned safely.

The little blue folks on Oa claimed the Source Wall bordered the Sea of Light, a cosmic pool of all emotional spectrum energies. Go there, and you’d never return.

The big shots said so, and the Book of Oa backed it up, so no one questioned it. The Lantern Corps stayed in their little corner of the universe, bickering and battling among themselves, draining their energy in endless squabbles.