Alot of Blood Angels hate......
I would have to agree, I'm sure its a pact much like the one Magnus made. Tzeentch is always in for change, and at the very least getting followers from a Chapter one would consider "Kornate" in action. I highly doubt however, the whole Chapter will change. IF Mephistion made a pact, it will probably just include himself.
"Take a moment, please. Ponder the depths of your insignificance."
"It would be disappointing if you were unable to overcome this simplest of defenses. Hilarious, but disappointing."
Crimson Fists (C:SM)
WARMAHORDES (Skorne, Blindwater Congregation, Retribution of Scyrah)
DROPZONE COMMANDER (PHR)