Ring of arachnid control

A ring of arachnid control was a magical ring that allowed the wearer to control spiders.

Powers
As mentioned above, a ring of arachnid control gave the wearer the ability to control the action of spiders like they were under the effect of a ring of mammal control. The term "spiders" in this case applied to creatures who were magically changed into spider shape too.

The number of spiders, which could be brought under control depended on the spiders' size. If the subjected spider was a giant spider, only one could be controlled, if the spiders were of a normal size, a number between ten to forty could be controlled.

The ring could securely control spiders that were non-intelligent. When the spiders in question were intelligent, like creatures who polymorphed into spiders, could resist the control.

A few requirements needed to be met on the wearer's side to maintain control over spiders. First, the wearer needed visual contact with the spiders to be controlled. Second, the wearer needed to mentally concentrate on controlling spiders. This concentration forced him or her to refrain from any actions that could break it like spellcasting or engaging into combat. Even movement was restricted to slow one and all of it while maintain visual contact with the spiders under control.

If the concentration broke, the spiders were free from any control and did whatever they wanted including just running away.

A ring of arachnid control was a ring with charges. It was created with ten to hundred charges and every activation drained one charge. The ring could be activated once per hour for up to ten minutes. When the ring's activation broke, for example by breaking the concentration, a one hour gap between usages was required.

History
Rings of arachnid control were magic items associated with the drow.