Assassin's Curse (DC 15). The cursed, when under extreme emotional or physical duress, must make a Wisdom Saving Throw (DC 15) to avoid losing themself to the beast within. If successful, the cursed must continue to make saves for additional moments of duress that occur until a short or long rest has been completed (consult the DM for guidance, if needs be). Each additional check during that period increases the DC by 1. Upon a fail, the cursed undergoes an horrific transformation into a large monstrosity, mostly a serpent, but with the torso of a humanoid. Any equipment the cursed is wearing or carrying is absorbed into the transformation.
While the cursed is transformed into one of the Brood, they retain their personality and memories, but are not able to focus enough to draw from the skills and abilities they would have in their primary form. Instead, they gain the below abilities and are overcome by the need to do violence. If the source of their duress is something killable, they are compelled to make that creature their primary target but will otherwise attack whatever creature is nearest to them. The cursed reverts to their original form if they die or are rendered unconscious, they have killed their target and fed on it, or after 48 hours have passed.
Hold Breath. The Brood can hold its breath for 30 minutes.
Innate Spellcasting. While in this form, the cursed gains limited spellcasting ability based in Charisma with a spell save of DC 12. Those of the Brood can innately cast the following spells, requiring no material components:
At will: animal friendship (snakes only)
2/day: suggestion
1/day: fear
Multiattack. The Brood makes two melee attacks with their claws.
Bite. Melee Weapon Attack: +5 to hit, reach 5 ft., one creature. Hit: 6 (1d6 + 6) piercing damage plus 7 (2d6) poison damage.
Constrict. Melee Weapon Attack: +5 to hit, reach 5 ft., one creature. Hit: 7 (1d8 + 3) bludgeoning damage, and the target is grappled (escape DC 13). Until this grapple ends, the creature is restrained, and the Brood can’t constrict another target.
Claws (Natural Weapons). Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 6 (1d6 + 3) slashing damage.
Poison Spit. Ranged Weapon Attack: +5 to hit, range 30/60 ft., one target. Hit: 7 (2d6) poison damage.
Preternatural Speed. Twice per encounter, the Brood can choose to use their bonus action to either dash or take an additional attack action.
Opportunity Attack. The Brood can make an opportunity attack, using their claws, against a creature trying to leave their space.
No Escape. Using one charge of its Preternatural Speed ability as a reaction, the Brood can use their opportunity attack to reduce a fleeing creature's speed to 0, even if the creature takes the disengage action.
Description
The Brood of Maedran is a curse passed on by the bite of the Maedra Serpent, also called the Assassin Snake, as much for its deadly venom as for how it is often used by assassins of its native Meytan. The venom of the Maedra Serpent is almost always fatal, but in those rare occasions where its victim does survive, a curse takes hold that can turn the survivor into a monstrous killer.
At higher levels. This guide is for characters that have a Proficiency Bonus of +2. The Proficiency Bonus of the Brood of Maedra should always match the Proficiency Bonus of the character (including when leveling up), and all related ability checks, saves, attacks and DC's should increment accordingly, as should the damage dice used, to a maximum of a d10. The Brood of Maedra should also roll two additional d10s of hit points per raise in proficiency.
For example, a character with a Proficiency Bonus of +3 would have the following adjustments:
Hit Points: 10d10 +16 (if they previously had 60, they would now max at 80)
Saving Throws: DEX +5, CON +5
Skills: Perception +3, Stealth +5
Attacks: All attacks are now +6 and use d8's (except Constrict which will move to a d10). Next raise in Proficiency Bonus will bring all attack damage dice to d10's.
DC's: The Constrict DC is now 14, Spellcasting DC is 13, and the base DC for resisting the Assassin's Curse is now 16.