I didn't realize that Titan bubbles could be taken down with a certain amount of damage. I thought they were invincible. Goes to show you what little time I spend in the Crucible. Can they be taken down with weapon damage in PVE as well?
I don't think they go down from damage in PVE, just time. They do in PVP to supers because something has to counter them, or they would be very overpowered in some game modes.