It seems like Karakas has found a home in almost every deck imaginable. The option to bounce a legendary creature is extremely powerful.
Who cares if the land taps for white, and you're playing Simic Turbo Depths? Hell, you can bounce your own Marit Lage if you want to.
Despite its auto-include status, Karakas is not currently on the rules council's watch list. But that's fine with me! I just purchased my fourth copy. I'm going to shoehorn this bad boy into every deck I have, even if it's UBRG.