This spell magically bars a door, gate, or valve of wood, metal, or stone. The magical closure holds the portal fast, just as if it were securely closed and locked. Any extraplanar creature (djinn, elemental, etc.) with 4 or more Hit Dice can shatter the spell and burst open the portal. A Wizard Hero Points of 4 or more experience levels higher than the spellcaster can open the held portal at will. A Knock spell or a successful Dispel Magic spell can negate the hold portal. Held portals can be broken or physically battered down.