Collar Bell wakes up every creature in 30-ft. radius around the user from sleep, but only if they fail a save vs spell. Failing that same roll also causes deafening for 1 turn (10 rounds). Both effects are considered nonmagical and have power level 0. As such, they bypass Magic Resistance and can affect even Rakshasa and Liches/Demiliches. Moreover, the effects aren't considered hostile, so it won't turn blue-circle creatures red.
It's a reward from Barad Ding's Eight Cats side quest in Hidden Refuge.
Description[]
| “ | The wild mage Barad Ding was fond of cats, surrounding himself with the yowling beasts. Feral and undomesticated, his pets would often wander off, disappearing for days and filling Barad with concern. After weeks of worry, he decided to affix leather collars with tiny, magical bells on his companions. Whenever Barad would utter the command word, all bells in a certain radius ring melodically, revealing their locations. While enchanting the bells, Barad's magic was sometimes warped by wild surges, some harmless, some less so. The surge that erupted when he crafted this particular bell amplified Barad's magic to the extreme—instead of a soft tinkling, it emits a deafening burst of sound, capable of instantly waking anyone even from their deepest slumber. |
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