There's a bug right now where the arrow sometimes kills the player on it's way back. I'm working on a patch that should fix that as well as a bunch of other bugs, but this one has been kicking my butt for the past couple days. It's really hard to reproduce and I keep thinking it's fixed but it'll randomly happen again an hour later. I should have it fixed in an upcoming patch this Friday though.
Really sorry about this, I know it's super annoying.