New Monster: Arcanasite

Nimble slipped the ruby ring from the bandit king’s finger. “He was half right” he said with a crooked smile.

“About what?” Allianora asked, confused.

“He said we’d have to pry it out of his cold dead hands” Lifting the limp arm he continued “still warm.”

Rathgar chuckled as he wiped his blade clean on one of the bandit’s black and yellow checkered sash. “Where did Feris get to?”

“He was in the witch’s room” Allianora pointed “probably looking for her spell book.

Rathger sheathed his blade and walked over to the doorway. The witch’s body was still in the ruined protective circle, her blood mixed with the wax from the candles. Feris sat against the far wall, a large tome upon his lap.

“Feris, I-” Rathger froze. “What’s on your neck?”

“I’m not sure.” Feris’ voice rasped dryly. The greyish lump’s tendrils stretched from the crook of Feris’ neck up to his ear, and down under his shirt. “It feels weird though... and... I think it’s trying to talk to me.”

“Nimble! Allianora!” Rathgar barked. They rushed into the room and looked at Feris.

“Frelling-” Nimble said, as he drew his dagger and stepped toward Feris.

Feris tensed. “No-no-no-no-no! Leave it!!” he hissed, placing his hand protectively over the lump.

Allianora and Rathgar exchanged worried looks.

Arcanasites are not humanoid-centric

They're also known to appear in various sci-fi settings

Arcanasite
(unattached)
Armor Class: 9
Hit Dice: 2* (S)
Move: 30' (10')
Attacks: 1 tendril
Damage: paralysis
No. Appearing: 1 (1)
Save As: MU9
Morale: 12
Treasure Type: nil
Intelligence: 14
Alignment: Chaotic
XP Value: 25*

Monster Type: Monster, Enchanted (Rare)
These parasitic outsiders will attempt to attach to an arcane spellcaster above others, but will settle for a non-spellcaster until it can find a more suitable host. It's touch causes paralysis, allowing it to settle itself on or around the host's head. Once attached, it will begin to draw sustinance from the host. In return it will boost the spellcaster's abilities. Arcanasites are able to communicate telepathically with those within 15', and it will attempt to convince spellcasters to let it meld with them voluntarily.

An arcane spellcaster with an arcanasite attached will have an extra 2 spell slots/spell level available to them for 1st-3rd level spells, and an extra spell slot/spell level for spells of 4th-6th level. Additionally it has it's own knowledge of the arcane which it will use to assist in the creation of magical items or researching unique spells (usually a +5%-15% success rate or reduction in cost).

In return, the arcanasite will permanently drain 1 point of strength or constitution (50% chance) for every spell slot granted to the spellcaster. The host (and anyone with them) will also suffer a -2 to their reaction rolls. Additionally the arcanasite will have it's own agenda. The destruction of rival wizards is always top of their agenda. Hosts must either comply with the arcanasite's wishes or suffer a -2 to all rolls, an inability to cast spells, and even 1d2 points of damage/round for really stubborn hosts. Being both evil and intelligent, they will also allow the spellcaster to pursue their own agendas, as a happy host is a willing host. Wizards and other arcane spellcasters have a love hate relationship with Arcanasites due to the boon they offer and the price they eventually exact.

Non-spellcasters will suffer a permanent point of ability drain (con or str), the reaction roll penalty, and will be compelled to find it a more suitable host as quickly as possible.

Removal of an arcanasite requires a remove curse cast by a spellcaster at least 2 levels higher than the current host. Removing it physically is possible, but the host will suffer an equal amount of damage as the arcanasite, and must make a saving throw vs death rays or die in the process.

*Spellcaster hosts of arcanasites will have an additional * for every 2 spell slots provided by the creature.