Immobilized is one of the Afflictions in Pillars of Eternity 2: Deadfire. Afflictions are explicitly bundled sets of status effects that can be applied to, suspended, or fully removed from a character. While some afflictions have explicit overriding or exclusivity rules, most afflictions can co-exist with other afflictions.
Immobilized characters can't move and have -5 Dexterity.
Immobilized Notes & Tips