First, let me clarify: by don't move I only meant do not use your left stick, you can still use your right stick for aiming purposes :) I don't know if it's a glitch or not but if you move via your left stick you can be damaged and even killed by Atheon while under the relic's bubble. With that said, the most common reason I've seen players die inside the relic bubble is they attempt to shoot rocket launchers either on purpose while under the relic bubble because they don't know better or when they attempt to pop their heads out of the bubble "real quick" to shoot their rocket launcher. Tip here: never try a rocket launcher anywhere near a bubble :) As for the relic bubble splash damage, I have two theories that are covered if you just stand still: 1) moving using your left stick anytime after entering the bubble will somehow allow the splash damage from Atheon's shots to damage you or 2) while you're moving using your left stick while under the relic bubble splash damage will hurt you. In either case it's best to just jump in and don't use the left stick :) Hope that helps!