Rika Shiguma

The Anime
Seeker is the least formidable of Marik's Rare Hunters, but has three sets of Exodia cards in his deck. However, it is later revealed these cards are fake, and the cards are marked. Seeker jumped Joey Wheeler on his way to see his sister Serenity, and dueled him. He won using Exodia, and took his Red Eyes Black Dragon.

Yugi dueled him at the start of Kaiba's tournament, Battle City, but he forbad Joey to tell Yugi that he had Exodia in his deck, threatening to tear his Red Eyes to pieces if he did. However, Yugi figured it out anyway, and became the first person to defeat Exodia in any way, and won the duel. As punishment for his failure, Marik took over his body and banished his soul to the Shadow Realm.

He later appeared as a lost soul in Season 4, Waking the Dragons, as Yami was trying to get to Yugi in a circle of lost souls, however it is likely that he was just an illusion, as many of the others were neither dead nor in the Shadow Realm or taken by the Orichalcos. Though it is possible his soul was banished to the Shadow Realm after he failed Marik.

Falsebound Kingdom
Seeker also appears as one of Scott Irvine's followers in Yu-gi-oh! Falsebound Kingdom and named as Rare Hunter. He appears in both Yugi and Kaiba's campaign in the level after Emperor Haysheen is defeated and Scott reveals himself. In Yugi's campaign, he is the boss in the level "Refugees" in the Uruvie Canyon. He tries to capture Tea and sends several soldiers to capture her. If she can get to Yugi's fort in time, Seeker would give up and leave and the level's completed. If she doesn't go in the fort, then all his soldiers must be defeated and then he must be fought. It is likely Scott 'erased' him after failing him.

In Kaiba's campaign, he appears with the same amount of soldiers with the same monsters in the Maryah-Denn region. After a certain amount of time, Yugi appears and half of Seeker's army is deleted, giving Kaiba the chance to fight him in the same manner. He does not use Exodia like in the anime, but the monsters: Dungeon Worm, Monster Tamer and Cybersaurus.