Symbiotic (3.5e Creature Subtype)
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 Symbiotic Subtype
A creature with the Symbiotic subtype is a Symbiotic, independent creatures that while symbiotic can survive without a host for a limited time. The Symbiotic is similar to the Symbionts subtype, however there are many small differences.
A symbiotic possesses the following traits (unless otherwise noted in a creature’s entry):
- Attach to host/Remove from host: Both of these usually cause some ability score damage and maybe some HP damage.
- Symbiotic creatures have an Ego Score as determined by mental ability bonuses (see below).
- Symbiotic creatures need to eat, sleep, and breathe. When attached to a host this is done when the host eats and sleeps.
- Host Dependency:Symbiotic creatures cannot survive without a host for a prolonged period of time. The symbiotic loses 1 Constitution point every 24 hours it goes without a host. Constitution Damage done in this fashion can't be regained through any natural or magical means.
- Transfer spell-effects: When the symbiotic is targeted by a spell or spell-like ability(whether it is harmful or helpful) the host is affected instead of the symbiotic creature. The symbiotic can't become the target of a spell that was directed at the host, however, unless the spell or spell-like ability has a target of self, effect personal. Only the host's spells and spell-like abilities affect both the host and symbiotic creature in this manner. No other spellcasters can cast spells on the host and the symbiotic creature.
- Ego Score: The symbiotic creature gains an Ego Score which determines how strong the Symbiotic creature's control over the host's body is. The Ego score is determined as follow:
- The symbiotic creature's Intelligence modifier, Wisdom modifier, and Charisma modifier are added to together, and this total becomes the base Ego Score.
- The Ego modifiers are as follow: for each Extraordinary Ability and special attack the symbiotic creature posses add 2 to the Ego Score, for each special trait add 1 to the Ego Score (symbiotic traits listed on this page do not count as special traits for the purposes of the ego score), and if the symbiotic creature has the type Outsider add 4 to the Ego Score.
Ego Vs. Will roll
The Ego score determines how hard it is to resist the mental sways of the symbiotic creature. When the symbiotic creature doesn't like the host's action it can attempt an Ego Vs. Will roll. The symbiotic creature rolls 1d20+Ego against a Will save roll by the host.
- Failure of the host results in the symbiotic creature having complete control over the body of the host. (The host can still take purely mental actions). The host can make another Ego vs. Will roll in a number of rounds equal to the symbiotic creature's ego score (minimum of 1 round) to attempt to regain control.
- Success by the host results in the symbiotic creature being unable to attempt another Ego vs. Will roll for a number of rounds equal to the symbiotic creature's ego score.