Deletion of Undermountain (2nd nomination)

Comment: or '''merge''' to Waterdeep per above comments since there are  to retain, per  and 
Stance: keep
Cited policy: Wikipedia:Reliable sources (WP:RS||WP:PRESERVE||WP:ATD)

Comment: insufficient RS to demonstrate 
Stance: delete
Cited policy: Wikipedia:Notability (WP:SIGCOV)