UPDATE. REVELATIONS OF VARYING IMPORTANCE.

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uu's name is Caliborn.
To everyone's complete lack of surprise, uu's weapon is a pool cue that doubles as an assault rifle.
Cherubs are strong and hardcore enough to gnaw off their own leg

Lord English can destroy Dream Bubbles, and presumably permakill anything living in them.
The shards from the destruction have apparently been whats killing the horrorterrors.

The sheer glitchyness of a 1 player session created a black hole?
That dreambubble was blue. The one that Aranea and Meenah were in was purple.