From TFCWiki - The Final Challenge MUD's Player Information Resource
Become able to walk through a solid door.
Characters and mobs with Pass Door will be Translucent.
Pass door is available to:
Mages : level 18. Any Alignment.
- Cannot be cast on other characters or mobs. At level 30 mage this spell costs 20 mana and causes the player to be able to walk through certain doors as if the door did not exist. - Ink, added 05/24/2012