Greyheart Tidecaller

Greyheart Tidecallers are Broken found in Serpentshrine Cavern.

Abilities

Frostbrand Attack — Imbue the Shaman's weapon with frost. Each hit has a chance of causing 1059 additional Frost damage and slowing the target's movement speed by 25% for 15 sec. Lasts 30 minutes.
Poison Shield — Protects the caster with a poisonous shield. When a spell, melee or ranged attack hits the caster, the attacker will be poisoned. This expends one poison ball. Only one ball will fire every few seconds. Lasts 2 min.
Virulent Poison — Infects the target, dealing 1415 Nature damage every 3 sec.
Water Elemental Totem — Summons a Water Elemental Totem.

They have a chain lightning that silences everyone it hits but doesn't hit particularly hard.
They drop water elemental totems, which have around 5k health and spawn elite water elementals. The elementals can be CC'd normally and despawn with the totem is killed.

These are vulnerable to polymorph and fear.
Immune to hunters freezing traps, but are affected by frost trap. Entrapment can also proc on them.