Yami Bakura  

Dark Bakura, King of Thieves, Spirit of the Ring, Thief Bakura, Tozoku Ou, 闇の獏良

The mysterious dark entity residing in the Millennium Ring seeks out all other items from the same series. Despite its unclear motive, it's evident that its intentions are malicious. When fully possessing Bakura's body, this spirit can harness powers of the Shadow Realm and bring them into our world. It has established a connection with Bakura through the Millennium Ring, allowing it to return whenever needed or lost. This entity is Yami Yugi's primary adversary, fueled by a 5,000-year vendetta against him.