AD&D 2nd Edition

Range: 60 yds
Components: V
Duration: Special
Casting Time: 1
Area of Effect: 10 sq. ft/level
Saving Throw: None

The knock spell opens stuck, barred, locked, held, or wizard-locked doors. It opens secret doors, as well as locked or trick-opening boxes or chests. It also loosens welds, shackles, or chains. If used to open a wizard-locked door, the spell does not remove the former spell, but simply suspends its functioning for one turn. In all other cases, it permanently opens locks or welds – although the former could be closed and locked again later. It does not raise barred gates or similar impediments (such as a portcullis), nor does it affect ropes, vines, and the like. Note that the effect is limited by the area; a 3rd level wizard can cast a knock spell on a door of 30 square feet or less (for example, a standard 4 ft x 7 ft door). Each spell can undo up to 2 means of preventing egress through a portal. Thus, if a door is locked, barred, and held, or triple locked, opening it requires 2 knock spells. In all cases, the location of the door or item must be known – the spell cannot be used against a wall in hopes of discovering a secret door. The reverse spell, lock, closes and locks a door or similar closure, provided there is a physical mechanism. it does not create a weld, but it locks physically operated locking mechanisms, set bars, and so on, up to 2 functions. It cannot affect a portcullis.