Stone of Monster Summoning (3.5e Equipment)
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"Oh whatever shall I do with all this Treasure and me with no armor and low on hit points"- Verbal component for 0-level Monster summoning
 The Stone Of Monster Summoning
This artifact, created by the same student who invented the Snappy Comeback Turtle, is actually a common black rock with a very low level spell cast upon it. He would give this to anyone who attempted to intimidate him into aiding them in their many magical ventures, such as passing exams. The stone has one charge for a custom spell of his own invention
 0-level Monster summoning
In order to activate the stone, the user must chant the above words, upwards of three times. When the spell takes effect, the stone will disintegrate, showing the spell is working.
0-level monster summoning will draw to it any creature in the area, usually the most powerful ones it can find. It is completely at random (ie. DMs choice). They appear in the same manner that other summoned creatures would appear, in a puff. Unfortunately for the caster, the summoned creature has no binds to the caster, and will always attack him/her first.
Unless the DM deems it otherwise, the item is meant to produce problems, not solutions.
The spell will not draw any creature that would not already appear in the area the spell is cast in.
For added irony, the DM may choose to have an exceedingly overpowered creature appear, just for fun.
 DM Notes
These stone were originally another piece of plunder from the magical school raid. We had a great deal of fun pawning them off to merchants as a 'Grand monster summoner'.
We, of course, learned the truth about these items when we used them in a fight against a summoning teacher.
In retrospect, it would make sense for a Tanniri to appear in a classroom dedicated to poking around in the bowells of the Abyss.