Regeneration. The vampire regains 5 hit points at the start of its turn if it has at least 1 hit point and isn’t in sunlight or running water. If the vampire takes radiant damage or damage from holy water, this trait doesn’t function at the start of the vampire’s next turn. If the chest of Tamoachan is opened, the vampire instead regains 10 hit points.
Mask of Shadows: The vampire can assume an illusionary form friendly to others for the purposes of manipulation. Once per day the vampire can cast Disguise Self (DC15) to assume the appearance of a person friendly to the party.
Multiattack. The vampire makes three melee attacks, only one of which can be a bite attack.
Bite. Melee Weapon Attack: +7 to hit, reach 5 ft., one willing creature, or a creature that is grappled by the vampire, incapacitated, or restrained. Hit: 7 (1d6 + 4) piercing damage plus 7 (2d6) necrotic damage. If the target is humanoid, it must succeed on a DC 15 Charisma saving throw or be charmed by the vampire for 1 minute. While charmed in this way, the target is infatuated with the vampire.
The target’s hit point maximum is reduced by an amount equal to the necrotic damage taken, and the vampire regains hit points equal to that amount. The reduction lasts until the target finishes a long rest. The target dies if its hit point maximum is reduced to 0.
Rapier. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 8 (1d8 + 4) piercing damage.
Unarmed Strike. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 7 (1d8 + 3) bludgeoning damage. The vampire can also grapple the target (escape DC 14) if it is a creature and the vampire has a hand free.
Call of the Emperor (1/Day): The vampire raises undead servants to battle along side it. If the chest at the top of the Hidden Shrine of Tamoachan is opened before combat begins, this action raise 1d6 Zombies. If the chest is not open, this action raises 1d6 Crawling Claws instead.
Parry. The vampire adds 3 to its AC against one melee attack that would hit it. To do so, the vampire must see the attacker and be wielding a melee weapon.
The vampire can take 1 legendary action, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature’s turn. The vampire regains spent legendary actions at the start of its turn.
Unarmed Strike. The vampire makes one unarmed strike.
Shadowstep. So long as the vampire is in dim light or darkness, it can wrap the shadows around itself to teleport up to 30 feet to an unoccupied space.
Description
Once feared and worshipped as a god of undeath and shadows in bygone ages, this vampire is the last challenge awaiting those that would travel to the top level of the Hidden Shrine of Tamoachan. The vampire may initially appear in a harmless or friendly form to convince the party to open the great chest of the shrine nearby, thereby releasing more of its evil power sealed away long ago.
modified Blood Drinker Vampire from Ravinica, for use as a final boss in HSoT. Could maybe be considered a CR 9 creature due to its summoning action and Legendary Actions?