Invocation Grade: Lesser
Equivalent Spell Level: 3rd
So named for the people who most commonly suffer its effects, this invocation allows you to make a deadly trap of an ordinary door. You can produce a hold portal effect, as the spell. In addition, should anyone other than you open the ensorceled portal from the outside by any means (including knock or dispel magic spells) before the spell’s duration expires, the portal (or a large portion thereof) instantly explodes outward, dealing 5d6 points of damage to all within 20 feet of the door on that side. Creatures standing on the inside of the door are unaffected. Each creature but the one that triggered the effect (assuming it was standing in front of the door) can attempt a Reflex save for half damage. Spell resistance does not apply to the damage caused by this effect.
Source: Cityscape, page 68.