Hellboy 7 drop text says when he comes into play you may return all characters in play to their owners- can this resolve before the uniqueness rule so that my 4 drop Hellboy goes to my hand instead of the discard pile?

Cost: 7 Hellboy, The Right Hand of Doom
Team: B.P.R.D.
Ranged
ATK: 16
DEF: 14
When Hellboy enters play, you may return all other characters you control to their owners' hands. If you returned at least one B.P.R.D. character, stun target character with cost 6 or less.
Whenever Hellboy stuns a character, put a doomsday counter on or remove a counter from target resource named Project Ragna Rok.


EHB-006 Illustrator: Mike Mignola Rare

The uniqueness check comes in before any triggered effects come into play. Hellboy 4 would be sent to the KO pile by Hellboy 7 before Hellboy 7's ability came in. There was a recent thread about this http://www.vsrealms.com/forum/showthread.php?t=49743