Katy Perry Performs "Roar" with Tegan and Sara and Ellie Goulding Live

Katy Perry brought out Tegan and Sara, Ellie Goulding, Sara Bareilles and Kacey Musgraves on stage last night (October 23rd) at her We Can Survive benefit show in Los Angeles, CA to perform "Roar".

You can watch a video of this amazing performance below.