Colloidal Guardian

Crystalline Echo Field (Recharge 5-6).

The Guardian emits a burst of resonant energy in a 20-foot radius. Each creature in that area must succeed on a DC 15 Wisdom saving throw or take 10 (3d6) psychic damage and have disadvantage on the next Intelligence or Wisdom check or saving throw it makes before the end of its next turn.

On a successful save, the creature takes half damage and no penalty.

Phase Shift (1/day).

The Guardian partially phases into the Colloid's echo dimension for 1 minute.

- It can move through unworked stone as if it were difficult terrain.- It gains resistance to all damage types except force.

Harmonic Body.

When the Guardian takes lightning or thunder damage, roll a d6. On a 5 or 6, it releases a resonance shockwave: All creatures within 10 feet must succeed on a DC 15 Strength saving throw or be knocked prone.

**Multiattack.** The creature makes two attacks: using *Crystalline Slam* and *Reverberate Bolt* in any combination.

**Crystalline Slam.** Melee Attack Roll: +8, reach 5 ft.
Hit: 14 (2d10 + 3) bludgeoning damage plus 7 (2d6) psychic damage.

**Reverberate Bolt.** Ranged Attack Roll: +7, range 90 ft.
Hit: 18 (4d8) psychic damage.
The target must succeed on a DC 15 Wisdom saving throw or be silenced until the end of its next turn (it cannot speak, cast spells with verbal components, or use telepathy).

Shatter Spike (Bonus Action, 1/Turn).

After hitting a creature with a melee attack, the Guardian may drive jagged crystal into the target.

Until the end of that creature's next turn:

- Its speed is reduced by 10 feet.

- If it moves more than 10 feet, it takes 1d6 psychic damage.