RangerWickett
Legend
astriemer said:Anti-Entrance Stone
This magic item prevents the use of commonly available spells to secure entrance to an area that you want guarded. It protects a small room and as it prevents a spell, it sets off an alarm to indicate an intrusion attempt.
Targeted Dispel Magic versus Move Space, Scry, Move Earth (1 MP each). The creator has 8 ranks in Dispel Magic. (SR 19 or +9 Scry DC)
Contingent Create Sound (5 MP)
Total MP 9 (8 + 1 for duration).
81,000 gp base value
You've overcosted a bit, I think.
You want an item that is Dispel Magic 3/Create Sound 1/Gen 3. You get targeted antimagic (Move Space, Scry, Move Earth) for 3 MP, an alarm as loud as shouting men for 1 MP, contingency for 1 MP, a 10-ft. radius for 1 MP, and the minimum duration for 1 MP. That's an expensive version.
The cheap version is Dispel Magic 1/Gen 2, 9000 gp to ward a room against teleportation fairly well.
If you want to shell out the big bucks, for 400,000 gp you can get Dispel Magic 3/Create Sound 2/Gen 15. That gets you local area (800-ft. radius), a very loud contingent alarm, (if a mage with 23 ranks in Dispel Magic makes it) SR 33 for worrisome spells, and the discerning enhancement so the alarm only goes off in the right areas.
Of course, there's still always Transform Earth to just reshape the stone walls.
In the skills-based modern EOM I'm working on, I've limited a few really game-altering effects like teleportation to feats.