It seems like so long ago that Deathstorm, the Black Lantern Firestorm, stole the White Lantern and ran off to Qward under the orders of a mysterious master. Now, at the beginning of Brightest Day #22 we find out who it is, and to be honest, it’s not too big of a shocker.
It’s the Anti-Monitor! His plan apparently involves using the Lantern to create life to empower himself via consumption, possibly even making himself more powerful than he was during the Crisis.
The thing is though….the White Lantern has its own form of sentience, and it seems it wanted to be brought there so it could gather information on the Anti-Matter universe.