Practitioners of Iggy Azalea schadenfreude had a big reason to lol yesterday when Britney Spears fired back at her comments regarding the relative bricking of their song "Pretty Girls." While she didn't address Iggy directly, the timing of this tweet is too coincidental to not be a thinly veiled shot at Iggy. The Internet was ablaze in hailing Britney as the ultimate Shade Queen, and for good reason: the veteran pop star has a long and storied history of throwing both subliminals and straight-up shots at fellow pop stars, ex-boyfriends, and anyone in general who wants it. #YouWantAPieceOfHer? Well, be careful what you ask for. Here are the five best times Britney stepped in the ring and handled someone who tried to bring it to her.