Krull

Medium Humanoid (Tortle), Lawful Evil

STR
20 (+5)
DEX
14 (+2)
CON
15 (+2)
INT
12 (+1)
WIS
20 (+5)
CHA
12 (+1)
Hold Breath.

Krull can hold his breath for 1 hour.

Inescapable Destruction.

Necrotic damage dealt by Krull's spells ignores resistance to necrotic damage.

Spellcasting.

Krull is a 14th-level spellcaster. His spellcasting ability is Wisdom (spell save DC 16, +8 to hit with spell attacks). He has the following cleric spells prepared:

Cantrips (at will): chill touch, mending, resistance, sacred flame, spare the dying, thaumaturgy

Level 1 (4 slots): cure wounds, detect evil and good, false life, inflict wounds, ray of sickness

Level 2 (3 slots): blindness/deafness, gentle repose, hold person, ray of enfeeblement, spiritual weapon

Level 3 (3 slots): animate dead, magic circle, speak with dead, spirit guardians, vampiric touch

Level 4 (3 slots): banishment, blight, death ward, divination, locate creature

Level 5 (2 slots): antilife shell, cloudkill, contagion, greater restoration

Level 6 (1 slots): create undead, true seeing

Level 7 (1 slots): divine word, regenerate

Actions

Claws.

Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 7 (1d4 + 5) piercing damage.

+1 Maul.

Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: 13 (2d6 + 6) bludgeoning damage plus 9 (2d8) necrotic damage.

Shell Defense.

Krull withdraws into his shell. Until he emerges as a bonus action, he has a +4 bonus to AC and has advantage on Strength and Constitution saving throws. While in his shell, Krull is prone, his speed is 0 and can't increase, he has disadvantage on Dexterity saving throws, he can't take reactions, and the only action he can take is to emerge from his shell.

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Krull

Source: Baldur's Gate: Descent Into Avernus, p. 110 - Licenses and attribution