Death Throes. When the gauth dies, the magical energy within it explodes, and each creature within 2 meters of it must make a Difficulty 14 Reflex saving throw, taking 4 (1d8) force damage on a failed save, or half as much damage on a successful one.
Spellcasting. The gauth uses Psionics (Int) to cast spells (spell save Difficulty 13, +4 to hit with spell attacks). It has 6 mana, a mana limit of 1, regains all expended mana when it finishes a long rest, and regains half its total mana when it finishes a short rest. It knows the following spells:
Stunning Gaze. If a creature starts its turn within 5 meters of the gauth and the two of them can see each other, the gauth can force the creature to make a Difficulty 14 Will saving throw if the gauth isn’t incapacitated. A creature that fails the save is stunned until the start of its next turn.
Unless unaware of the gauth, a creature can avert its eyes to avoid the saving throw at the start of its turn. If the creature does so, it has disadvantage on attack rolls against the gauth until the start of its next turn. If the creature looks at the gauth in the meantime, it must immediately make the saving throw.
Bite (1/turn). Melee Weapon Attack: +4 to hit. Hit: 11 (2d8 + 2) piercing damage.
Eye Rays (1/turn). The gauth shoots three of the following magical eye rays at random (reroll duplicates), choosing one to three creatures it can see within 20 meters of it:
Devour Magic Ray: The targeted creature must succeed on a Difficulty NaN Reflex saving throw or have one of its magic items lose all magical properties until the start of the gauth’s next turn. If the object is a charged item, it also loses 1d4 charges. Determine the affected item randomly, ignoring single-use items such as potions and scrolls.
Enervation Ray: The creature must make a Difficulty NaN Fortitude saving throw, taking 31 (7d8) necrotic damage on a failed save, or half as much damage on a successful one.
Pushing Ray: The targeted creature must succeed on a Difficulty NaN Reflex saving throw or be pushed 3 meters directly away from the gauth and have its speed halved until the start of the gauth’s next turn.
Fire Ray: The creature must make a Difficulty NaN Reflex saving throw. On a failure, the creature takes 31 (7d8) fire damage and is burning 2. On a success, a creature takes half as much damage and isn’t burning.
Paralyzing Ray: The creature must succeed on a Difficulty NaN Fortitude saving throw or be paralyzed for 1 minute. The creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.
Sleep Ray: The creature must succeed on a Difficulty NaN Will saving throw or fall asleep and remain unconscious for 1 minute. The creature awakens if it takes damage or another creature uses an action to wake it. This ray has no effect on constructs and undead.
As a reaction, which you use when a creature that you can touch or see within 10 meters casts a spell, you can dampen the spell, making it easier to avoid or resist. The attack is made with disadvantage or each creature makes the first saving throw against the spell with advantage. You can do so after the roll but before any effects of the roll occur.
If the roll already has advantage or disadvantage, you cannot apply another instance of advantage or disadvantage and you must use this before the roll to cancel out any advantage or disadvantage.
Counterspell. You can expend 1 additional mana to attempt to interrupt the spell instead of dampen it. Make an ability check using your spellcasting skill. The Difficulty equals the creature’s spell Difficulty + the spell’s effective mana. If you have identified the spell being cast, you have advantage on this ability check.
On a success, the creature’s spell fails and has no effect.
On a failure, you dampen the spell as normal.
A spell’s effective mana is normally the amount of mana it was cast with, including augmentation. If a feature lets a spell be cast without expending mana then the spell’s effective mana is its normal mana cost.
You gain a +1 bonus to your ability check for each additional mana expended.
As an action, you sense the presence of magic within 5 meters of you. If you sense magic in this way, you can use an action to see a faint aura around any visible creature or object in the area that bears magic, and you learn its theme, if any.
The spell can penetrate most barriers, but it is blocked by 30 centimeters of stone, 2 centimeters of common metal, a thin sheet of lead, or 1 meter of wood or dirt.
If you touch a creature or object for 5 minutes, you can determine the magic affecting it. If it is a magic item or some other magic-imbued object, you learn its properties and how to use them, whether it requires attunement to use, and how many charges it has, if any. You learn whether any spells are affecting the item and what they are. If the item was created by a spell, you learn which spell created it. If it is a creature, you learn what spells, if any, are currently affecting it.
As an action, you pull magical energy out of a creature that you can touch or see within 10 meters. The creature must make a Will saving throw. If the creature doesn’t have mana or psi, the spell has no effect on it.
On a failure, it takes 1d10 force damage, loses 1 mana or 2 psi, and has disadvantage on saving throws to maintain concentration on a spell until the end of its next turn.
On a critical failure, it takes twice as much damage.
On a success, it takes half as much damage.
On a critical success, it takes no damage.
If the creature has innate spellcasting with a set amount each day, use the highest level slot from that section to determine if the slot is lost.
You can increase the damage by 3d10 and the target loses 1 additional mana for each additional mana expended.
Antimagic Rebuke. You can expend 1 additional mana to cast the spell as a reaction, which you use when a creature that you can touch or see within 5 meters of you succeeds on a saving throw against a spell. The spellcaster is the target, the damage changes to 1d6, and additional augments increase the damage by 2d6 instead of the normal increase.