Another conversion for my own reference, but feel free to use it.
XANTHOCERAS
Legendary Resistance (3/Day). If Xanthoceras fails a saving throw, it can choose to succeed instead.
Rejuvenation. Xanthoceras has a phylactery (a shell stored in area 64) and if destroyed gains a new body in 1d10 days, regaining all his hit points and becoming active again. The new body appears within 5 feet of the phylactery.
Ironwood. Xanthoceras body is made from ironwood – a magically enchanted ash wood that appears charred. This wood is as strong as steel, however, it does make him vulnerable to fire.
Turn Resistance. The lich has advantage on saving throws against any effect that turns undead.
Spellcasting. Xanthoceras is an 18th-level spellcaster. Its spellcasting ability is Intelligence (spell save DC 20, +12 to hit with spell attacks). Over time, his link the positive energy plane has warped is magic to be more nature orientated, he has the following druid spells prepared:
- Cantrips (at will): druidcraft, mending, poison spray, produce flame
- 1st level (4 slots): cure wounds, entangle, faerie fire, speak with animals
- 2nd level (3 slots): animal messenger, beast sense, hold person
- 3rd level (3 slots): conjure animals, meld into stone, water breathing
- 4th level (3 slots): dominate beast, locate creature, polymorph (see Tulips below), stoneskin, wall of fire
- 5th level (3 slots): commune with nature, mass cure wounds, tree stride
- 6th level (1 slot): heal, heroes’ feast, sunbeam
- 7th level (1 slot): fire storm
- 8th level (1 slot): animal shapes
- 9th level (1 slot): foresight
Note: When saving against the spells of Xanthoceras, save at -1 for each Pc, hireling, henchman, or good friend a given Pc has seen die or disappear forever (maximum -8).
Actions
Paralyzing Touch. Melee Spell Attack: +12 to hit, reach 5 ft., one creature. Hit: 10 (3d6) cold damage. The target must succeed on a DC 18 Constitution saving throw or be paralyzed for 1 minute. The target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.
Heartbreaker (Lovesick) (1/Day). Subject’s heart freezes and shatters inside their chest. (Save allowed, recharges if it does not kill a target).
Weeping Ooze (Lovesick). Subject breaks down crying. Sadness oozes out of their nose and mouth, forms into ooze then attacks them. (Str equals # of dead Pc friends/ Npc good friends.)
Tulips (Lovesick). Xanthoceras uses the polymorph spell. When Xanthoceras uses Polymorph, his victims are always turned into massive tulips. Zamia’s favourite flower.
Hand of Baudelaire (Lovesick). PC sits right down cross-legged on the floor with their head bowed and scribbles poetry about everything that’s gone wrong in their life. No save. Spell ends when player completes their own piece of poetry of like type to the DM’s satisfaction, and not before. They may do so in their character’s voice.
Poltergeist Sigh (Lovesick). Victim compulsively sighs whenever they fail a roll. Each sigh breathes forth a minor depressive poltergeist that does nothing. It just holds you back whenever you try to achieve something imposing disadvantage on skill checks until the next long rest.
Legendary Actions
Xanthoceras can take 3 legendary actions, 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. He regains spent legendary actions at the start of its turn.
- Cantrip. Xanthoceras casts a cantrip.
- Lovesick. Xanthoceras uses any single action that has the lovesick tag.
- Paralyzing Touch (Costs 2 Actions). Xanthoceras uses its Paralyzing Touch.
- Frightening Gaze (Costs 2 Actions). Xanthoceras fixes its gaze on one creature it can see within 10 feet of it. The target must succeed on a DC 18 Wisdom saving throw against this magic or become frightened for 1 minute. Creatures of 5th level or lower (or CR 5 or lower) have disadvantage on this saving throw. While frightened the target runs until they can no longer see Xanthoceras. The frightened target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a target’s saving throw is successful or the effect ends for it, the target is immune to the lich’s gaze for the next 24 hours.
- Disrupt Life (Costs 3 Actions). Each non-undead creature within 20 feet of Xanthoceras must make a DC 18 Constitution saving throw against this magic, taking 21 (6d6) necrotic damage on a failed save, or half as much damage on a successful one.
Xanthoceras’s Lair
A lich often haunts the abode it favored in life, such as a lonely tower, a haunted ruin, or an academy of black magic. Alternatively, some liches construct secret tombs filled with powerful guardians and traps. Everything about a lich’s lair reflects its keen mind and wicked cunning, including the magic and mundane traps that secure it. Undead, constructs, and bound demons lurk in shadowy recesses, emerging to destroy those who dare to disturb the lich’s work. A lich encountered in its lair has a challenge rating of 22 (41,000 XP).
Lair Actions
On initiative count 20 (losing initiative ties), the lich can take a lair action to cause one of the following magical effects; the lich can’t use the same effect two rounds in a row:
- The lich rolls a d8 and regains a spell slot of that level or lower. If it has no spent spell slots of that level or lower, nothing happens.
- The lich targets one creature it can see within 30 feet of it. A crackling cord of negative energy tethers the lich to the target. Whenever the lich takes damage, the target must make a DC 18 Constitution saving throw. On a failed save, the lich takes half the damage (rounded down), and the target takes the remaining damage. This tether lasts until initiative count 20 on the next round or until the lich or the target is no longer in the lich’s lair.
- The lich calls forth the spirits of creatures that died in its lair. These apparitions materialize and attack one creature that the lich can see within 60 feet of it. The target must succeed on a DC 18 Constitution saving throw, taking 52 (15d6) necrotic damage on a failed save, or half as much damage on a success. The apparitions then disappear.
- Xanthoceras uses any single action that has the lovesick tag.