Tulvak

Coven (mental, occult) — A green hag adds Entangling Flora, Outcast's Curse, and Wall of Thorns to her coven's spells.

This monster can form a coven with two or more other creatures who also have the coven ability. This involves performing an 8-hour ceremony with all prospective coven members. After the coven is formed, each of its members gains elite adjustments, adjusting their levels accordingly. Coven members can sense other members' locations and conditions by spending a single action, which has the concentrate trait, and can sense what another coven member is sensing as a two-action activity, which has the concentrate trait as well.

Covens also grant spells and rituals to their members, but these can be cast only in cooperation between three coven members who are all within 30 feet of one another. A coven member can contribute to a coven spell with a single action that has the concentrate trait. If two coven members have contributed these actions within the last round, a third member can cast a coven spell on her turn by spending the normal spellcasting actions. A coven can cast its coven spells an unlimited number of times but can cast only one coven spell each round. All covens grant the 8th-rank Cursed Metamorphosis spell and all the following spells, which the coven can cast at any rank up to 5th: Augury, Charm, Clairaudience, Clairvoyance, Dream Message, Illusory Disguise, Illusory Scene, Scouting Eye, and Talking Corpse. Individual creatures with the coven ability also grant additional spells to any coven they join. A coven can also cast the Control Weather ritual, with a DC of 23 instead of the standard DC.

If a coven member's departure or death brings the coven below three members, the remaining members keep their elite adjustments for 24 hours, but without enough members to contribute the necessary actions, they can't cast coven spells.

Constant Spells — A constant spell affects the monster without the monster needing to cast it, and its duration is unlimited. If a constant spell gets counteracted, the monster can reactivate it by spending the normal spellcasting actions the spell requires.

+1 Status to All Saves vs. Magic —

Sound Imitation — A green hag who succeeds at a Deception check to Lie can mimic the sounds of any animal found near her lair. She has a +4 circumstance bonus to this check.

Betraying Touch — The green hag touches a creature that doesn't realize the hag is an enemy. The betrayed creature is affected by the hag's enfeebling humors and takes a -4 circumstance penalty to their saving throw against that effect.

Change Shape (concentrate, occult, polymorph) — The green hag can take on the appearance of any Medium humanoid woman. This doesn't change her Speed or her attack and damage bonuses with her Strikes, but might change the damage type her Strikes deal (typically to bludgeoning).

The monster changes its shape indefinitely. It can use this action again to return to its natural shape or adopt a new shape. Unless otherwise noted, a monster cannot use Change Shape to appear as a specific individual. Using Change Shape counts as creating a disguise for the Impersonate use of Deception. The monster's transformation automatically defeats Perception DCs to determine whether the creature is a member of the ancestry or creature type into which it transformed, and it gains a +4 status bonus to its Deception DC to prevent others from seeing through its disguise. Change Shape abilities specify what shapes the monster can adopt. The monster doesn't gain any special abilities of the new shape, only its physical form. For example, in each shape, it replaces its normal Speeds and Strikes, and might potentially change its senses or size. Any changes are listed in its stat block.

Enfeebling Humors (occult) — A creature damaged by a hag's claw must succeed at a DC 30 Fortitude save or be Enfeebled 1 for 1 day. On a critical failure, or if it gets hit again and fails its save a second time, it's Enfeebled 2 for 1 day.

Exhale Miasma (occult) — The green hag exhales a miasma of green vapors. Each living creature in a 15-foot cone is affected by her enfeebling humors (attemping a save as normal).

She can't use Exhale Miasma again for 1d4 rounds.

Unsettling Revelation (emotion, fear, mental, visual) — Frequency once per hour

Trigger Tulvak uses Change Shape to assume her natural shape

Effect Tulvak's transformation into her true form is particularly revolting and can sicken those who aren't prepared for it. All creatures within 30 feet of Tulvak when she takes this reaction must attempt a DC 30 Will save or become Sickened 1 (Sickened 2 on a critical failure).