It's sort of official: there's serious bad blood brewing between Taylor Swift and Katy Perry.
It all started when Swift told Rolling Stone that she penned a song on hew new album about an enemy in the world of music, someone who did “something so horrible” when she tried to “sabotage an entire arena tour."
Then, not long after these comments went public, Perry Tweeted a reference to Mean Girls and a "Regina George in sheep's clothing," who we're rather positive is Taylor Swift.
So the claws are pretty much out between two of the top-selling artists in pop music history.
Will things get uglier from here? Who will fire the next shot? And where does this feud rank among recent famous rivalries, which include Drake Bell HATING on Justin Bieber and Jimmy Kimmel trading barbs with Kanye West?
Flip around and decide now: