Wendigo Brand is a Unique Ring 1 in Diablo IV Season 15 for All classes. It comes from General Unique Pool - every Lair Boss (Initiate, Greater, Exalted, Belial) can drop it in addition to their dedicated table.
Unique power
Every 15 kills in the last [50 - 60] seconds increases your damage by 2%[x], and Attack Speed by 1%[+].
Affixes
Primary Core Stat
Maximum Life
Where it drops
General Unique Pool - every Lair Boss (Initiate, Greater, Exalted, Belial) can drop it in addition to their dedicated table