User blog comment:SilverHexxitFights/Which is Terraria's Hardest Boss?/@comment-1466854-20131111024519

Skeletron Prime, as an endgame-geared player, takes me longer to kill than any other boss. Plantera I really can't vote for. Given the opportunity to prep by widening up an area, it's not very hard to topple her even undergeared. Though I do admit, I was tempted to vote Pumpking based on the fact that you can have seven of them on you at once if you're not careful.

Couldn't really offer a fair opinion on the console-exclusives, I've never played on a console.