Urufu Fureimu Ringu

Urufu Fureimu Ringu (ウルフフレイムリング, Wolf Flame Ring) is one of the seven legendary rings forged by using a legendary wolf spirit. Its main ability is Burning and Degeneration, it also allows the user to open wolf flame type boxes. It takes the form of a ring which emitts a orange flame when ignited using spiritual energy.

Powers
Burning: This ring allows the ability of burning, which means the user can create vicious flames to ignite around his enemy by focusing his spiritual energy there. Being the most strongest ring, Zancrow has to use much more spiritual energy to ignite it due to how much power it has.

Degeneration: This ring allows the ability of degeneration, which means the user can create a flame which can slowly wear something down into nothing. It is mostly used to wear down shields quickly, to increase the speed of the degeneration Zancrow must use more energy.

Wolf Flame Box Unlocking: This ring allows the user to open wolf flame type boxes. This is the only ring which can open wolf flame type boxes as it was the only wolf flame ring made.

Behind The Scenes
This was based off of Katekyo Hitman Reborn's seven elements.