Choker (3.5e Alternate Class Feature)
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Replaces: In exchange for 2d6 sneak attack damage, a rogue can learn to choke foes.
Benefit: Constrict (Ex): A choke attack deals 1d4+2 (crit 18-20/x2) points of damage (and sneak attack damage) with a successful grapple check against a Huge or smaller creature. Because it seizes its victim by the neck, a creature in the choke hold cannot speak or cast spells with verbal components.
Improved Grab (Ex): To use this ability, a choker must hit a Huge or smaller opponent with an unarmed attack. It can then attempt to start a grapple as a free action without provoking an attack of opportunity. If it wins the grapple check, it establishes a hold and can constrict. Players receive a +4 skill bonus on grapple checks. A player's minimum grapple modifier is +2 with this feature.
A creature who has no air to breathe can hold her breath for 2 rounds per point of Constitution. After this period of time, the character must make a DC 10 Constitution check in order to continue holding her breath. The save must be repeated each round, with the DC increasing by +1 for each previous success. When the character fails one of these Constitution checks, she begins to suffocate. In the first round, she falls unconscious (0 hit points). In the following round, she drops to -1 hit points and is dying. In the third round, she suffocates.