Disclaimer. The mechanics present in this article are still a draft. They are very potent and as such require editing and testing before recommended use at your tables.
When the adventurers first enter Za'Ul's Sanctum located in a sealed chamber atop the Bone Spire, he pays them no heed. However, should the adventurers dispatch Za'Ul's sentry Golems, he will put aside his current experiment to play host to his uninvited guests.
"What a mess!"
Za'Ul hisses inside your minds as you feel a sudden oppressive glare upon you. Then you see him. A man standing atop the North most pedestal surveying your group and the smashed pieces of the golem strewn about.
"It would seem I'll have to silence you all myself."
You might have Za'Ul enter the initiative after the third to last golem is defeated. This way, the players have the golems well in hand, but cannot spend their entire next round devoting all of their attention to Za'Ul.
He appears to the adventurers in his illusory form, an idealized version of his appearance in life. However, as Za'Ul uses abilities that require souls though, his form flickers to that of his true lich appearance.
Za'Ul employs the following tactics to outwit, outmaneuver, and outmatch his adversaries...
The First Round
Za'Ul enters the combat quite annoyed at the intrusion of the players. While he uses his turns efficiently, they don't have his respect and don't warrant risking damage to his home. He tries to pick them off cleanly in the first round.
- He enters the combat with a legendary action. Za'Ul casts Wall of Force to split the melee combatants from the spell casters bisecting his sanctum in two.
- He uses his last Legendary Action before his first turn to cast mage armor on himself.
- Za'Ul uses his teleportation network to get to the same side of the wall as the player first so that he does not have to make a charisma save to teleport through the wall of force.
- On his turn, Za'Ul uses his bonus action to teleport to a caster with either a death ward placed on them or more than 100 hit points to foreshadow his access to Power Word Kill. If another caster tries to counterspell Za'Ul, he casts a counterspell of his own at 6th level (his default counterspell level).
- After the failed power word kill, Za'Ul starts to take the battle more seriously. He activates his Legendary Eminence and the players get their first glimpse of Za'Ul's undead visage.
- Za'Ul will retreat back into the teleportation network if he has enough movement.
The Second Round
Za'Ul likes to systematically remove enemy creatures from the fight, like taking pieces from a chess board. He likes to focus them down one by one, dismantling the enemy. He is "relentless." Now that he realizes that the players may be a formidable threat, he begins to act more meticulously.
- If a player has a strong passive ability active, Za'Ul uses dispel magic on it with one Legendary Action.
- If a melee combatant demonstrates an ability get close to Za'Ul despite the Wall of Force and his teleportation network, Za'Ul will use 2 Legendary Actions to cast dominate person on them. He commands them to go grapple the nearest spellcaster and attempt to restrain them.
- On Za'Ul's turn, if a creature is within melee of him, he attempts to use his Your Soul is Mine! attack. He then uses his bonus action to teleport out of melee range and retreats to his network.
Soulless. A creature with the Soulless condition has disadvantage on all saving throws. Additionally, a soulless creature exposed to direct sunlight takes 5d6 damage at the start of their turn as they are reduced to a pile of smoldering ash. A creature may end the soulless condition by reducing Za'Ul, the Lich King to zero hit points, thereby freeing all souls captured by him. A soul that has been placed in the Vault of Souls can only be reclaimed by destroying the vault.
The Following Rounds
Za'Ul casts his spells at will as the situation calls for. He resorts to more and more destructive magics as he becomes more desperate to kill the characters. As he begins to run lower on souls for regenerative use and casting he might start to fling fireballs more freely with little care for the books and other valuable items in his sanctum.
Any characters that attempt to meddle with one of his treasures attracts Za'Ul's immediate attention and he swiftly deals with them by casting any of banishment, dominate person, feeblemind, power word stun, etc...
