Siabrae

Tremorsense (Imprecise) 60 feet — Tremorsense allows a monster to feel the vibrations through a solid surface caused by movement. It is an imprecise sense with a limited range (listed in the ability). Tremorsense functions only if the monster is on the same surface as the subject, and only if the subject is moving along (or burrowing through) the surface.

Miasma (aura, disease, primal) — 20 foot. DC 37 Fortitude.

A creature that enters the aura or begins its turn there becomes Sickened 2 on a failure (or Sickened 4 on a critical failure). An animal, fey, or plant that rolls a failure gets a critical failure instead. Regardless of the result of the saving throw, the creature is temporarily immune to the siabrae's miasma for 1 minute.

Rejuvenation (primal) — When a siabrae is destroyed, they can attempt a DC 10 Flat (they automatically succeed if they're standing on blighted or diseased terrain, and automatically fail if they're standing on sacred ground). If the flat check succeeds, the siabrae's body crumbles to dust and absorbs into the earth. After 1d10 days, the siabrae's body reforms from a mass of unworked stone large enough to create a new body; this stone is in a random location within 1d10 miles of where the siabrae was destroyed. The siabrae emerges from the stone with a peal of thunder, though without any of their gear.

Void Healing — A creature with void healing draws health from void energy rather than vitality energy. It is damaged by vitality damage and is not healed by vitality healing effects. It does not take void damage, and it is healed by void effects that heal undead.

Blight Mastery — Any of the siabrae's spells or effects that would normally be restricted to affecting animals can also affect undead animals. Furthermore, any animals the siabrae takes the form of or summons appear to be diseased, malnourished, or even dead and rotting. (This doesn't affect their statistics.)

Earth Glide — The siabrae can Burrow through any earthen matter, including rock. When it does so, the siabrae moves at its full burrow Speed, leaving no tunnels or signs of its passing.

Steady Spellcasting — If a reaction would disrupt the siabrae's spellcasting action, the siabrae attempts a DC 15 Flat. On a success, the action isn't disrupted.

Stony Shards (curse, earth, incapacitation, primal) — Tiny shards break off the siabrae's antlers when they attack, lodging in the target's wounds and inflicting a terrible curse. A creature damaged by a siabrae's stone antlers Strike must succeed at a DC 37 Fortitude save or become Clumsy 2 for 1d4 rounds on a failure. If the creature critically fails, or fails while already clumsy 2 or greater, the creature is petrified.