User blog comment:UglyTurtle/Justice League of Equestria RolePlay Blog Part II/@comment-5837525-20141127195455

He said... "the days of the Power Ponies are numbered. They've caused too many conflicts... and must be destroyed."

(Copper gets a chill down his spine.)

I don't think it was Parlys. If he had a vendetta against the Justice League, it certainly never showed.