Symbiont Mastery
(Magic of Eberron, page 51, DnD 3.5)
[General]
You have stronger control over an attached symbiont than regular creatures, and you gain vitality for each symbiont attached to you.
Prerequisite
WIS 11
Benefit
You gain a +4 bonus on Will saves made during any personality confl ict that might erupt between you and your symbiont. You gain 2 bonus hit points per symbiont attached to you. If you detach a symbiont, you lose these hit points immediately.