If you cast your rift when standing on a small ledge or piece of geo with a lip on the bottom, the animation can play without actually casting your rift, forcing you to move and re-cast it. This usually results in you dying if you are in the middle of an engagement. This is a bug that has been around for quite some time, but it seems to have gotten worse for me in specific areas of Witch Queen. I play on the PC / Steam version of the game. The area I was able to reproduce this bug the most often was the final encounter of the Witch Queen campaign, specifically [spoiler]on the ground level area when behind cover during the DPS phases[/spoiler]. I reproduced this dozens of times while trying to complete this encounter. Usually, the collision behind cover is set up in a way that you can't just run/walk/slide onto those small lips unless you jump or land on them. In the rift cast animation, your left foot lifts up and then sets back down, and I'm not sure if it's an IK issue or what, but the character seems to get lifted up onto the ledge / lip around the platform in the process of that animation playing. So if you happen to be facing forward or pressing against a wall when you cast behind cover, or if you are peeking out to the right from cover so that your left foot would hit the lip during the animation, there's a reasonably high chance your character will move and the rift will not cast. I have video clips of this happening and would be happy to share but I also don't want to post spoilers of the ending in a place like this - so if there's a better place, please let me know. Thanks, and congrats to Bungie on an excellent expansion.