Brine Giant

Amphibious. The Giant can breath air and water.

Innate Spellcasting. The Brine Giant is a 4-level spellcaster. Its spellcasting ability is Wisdom (spell save DC 15, +7 to hit with spell attacks). The Brine giant has following spells prepared:
Cantrips (at will): Blur, Chill Touch 
1/day: Control Water, Misty step

Spiked Great club. Melee Weapon Attack: +10 to hit, reach 15 ft., one target. Hit: 24 (4d8 + 6) bludgeoning damage, and the target must make a DC 16 Con Saving throw, taking 33 (6d10) poison damage on a failed save, or half as much damage on a sucessful one 

Chill Touch. Ranged Spell Attack: +7 to hit, range 120 ft., one target. Hit: 18 (4d8) necrotic damage, and the target can't regain hit points until the start of the giant's next turn. if the target is undead, it also has disadvantage on attack rolls against the giant until the end of its next turn.

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