Magic Resistance. Celgir has advantage on saving throws against spells and other magical effects.
Marshal Undead.
Spellcasting. Celgir is a 15th-level spellcaster. His spellcasting ability is Charisma (spell save DC 19, +10 to hit with spell attacks). He has the following paladin spells prepared:
1st level (4 slots): command, compelled duel, cure wounds
2nd level (3 slots): hold person, zone of truth
3rd level (3 slots): dispel magic, revivify
4th level (2 slots): banishment, locate creature
Multiattack. Celgir makes three greatsword attacks with his Holy Avenger.
Holy Avenger. Melee Weapon Attack: +13 to hit, reach 5 ft., one target. Hit: 14 (2d6 + 7) slashing damage, plus 9 (2d8) radiant damage.
Parry. Celgir adds 4 to his AC against one melee attack that would hit him. To do so, he must see the attacker and be wielding a melee weapon.