Myrkul pretty much gets turned off while within hunger of hadar. doesn't use call of the damned or take any reactions.
preparation/buffs: potion of flying, sacred weapon, oil of combustion, sanctuary, elixir of bloodlust
level 5 paladin (devotion), 5 warlock (great old one)
knife of the under mountain King
sentinel shield
ne'er misser
risky ring
strange conduit ring
cloak of protection
yuan ti scale mail
boots of speed
diadem of arcane synergy
periapt of wound closure amulet