Corruption of Azim
Planar Ring of Fire
This item is a golden ring featuring a ruby with dancing flames in it. Once per week the ruby can be removed which causes the ring to become a portal to a keyed location on the plane of fire. The portal only stays open for ten seconds, after which it reverts back to a ring and drops to the ground. (Note that the user cannot take the ring with them as it becomes the portal.)
On the plane of fire, when the ruby is used at the keyed location, the portal reopens from wherever the ring is at that point. If it has been swept downriver, into an abyss, or if someone moved it that is where the new exit point is.