Okay folks, since no one is going to get it, the answer is Jason Woodrue, the Floronic man.
He's a scientist, specializing in botany.
He worked for the goverment when Swamp Thing was planning to wipe out all life to rebuild the earth in an attempt to stop him, and again in an attempt to contain Tefe' Holland.
He was commited to Arkham through most of Moore's run on Swamp Thing.
He taught at Gardner University, the alma matter of Alec Holland, Pamela Isley, and Dan Cassidy, the man who would become Blue Devil later in life.
He tapped into the green once and ran amock, attempting to kill all "meat" on the planet. Only the intervention of swamp THing stopped him.
He's from another dimension.
He's currently showing up in JLA as a member of the secret socity of supervillians, wich is a Crisis based Arc.
So I guess I should let someone else have a go at it.