Spells (3e)

When a power word, stun spell is uttered, one creature of the character's choice is stunned, whether the creature can hear the word or not. A creature with 50 or fewer hit points remains stunned for 4d4 rounds, one with 51 to 100 hit points is stunned for 2d4 rounds, one with 101 to 150 hit points is stunned for 1d4 rounds, and a creature with 151 hit points or more is not affected.

A stunned creature can’t act and loses any Dexterity bonus to AC. Attackers gain +2 bonuses to attack it.