Tide Ruler (5e Creature)
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Gargantuan elemental, unaligned
Saving Throws Str +11, Dex +1, Con +6, Cha +11
Avoidance. If the tide ruler is subjected to an effect that allows it to make a saving throw to take only half damage, it instead takes no damage if it succeeds on the saving throw, and only half damage if it fails.
Legendary Resistance (3/Day). If the tide ruler fails a saving throw, it can choose to succeed instead.
Magic Weapons. The tide ruler's weapon attacks are magical.
Multiattack. The tide ruler uses Call or Rule Tide and makes a push attack, or makes two call attacks.
Push. All creatures within 60 ft. of the tide ruler must attempt a DC 19 Dexterity saving throw. On a failure, the take 25 (3d8 + 11) bludgeoning damage and they move 30 ft. away from the tide ruler. The tide ruler may forgo dealing damage to double the distance moved.
Call (Recharge 5-6). The tide ruler calls out to the very water elementals inside every being. Each creature within 30 feet of the tide ruler that is not undead, a construct, or an elemental (except for water elementals) must succeed a DC 19 Charisma saving throw or drop to 0 hit points. On a successful save, the creature is frightened until the end of its next turn.
Rule Tide (Recharge 5-6). All creatures in a 60 foot long, 15 foot wide line must attempt a DC 19 Constitution saving throw. On a failure, they move 60 feet in the direction of the line.
As the smallest of water elementals formed currents in the seas of the elemental plane of water, they gradually coalesced into a manifestation of the currents themselves. These amorphous, vaguely-humanoid figures attempt to hold balance in the grand sea, only fighting those that would destroy the order of the realm, rather than any of its inhabitants that would engage in its natural chaos. Tide rulers that somehow find themselves in the physical world are often revered as polytheistic gods.