Pandora the Conjurer or Arkana (4Kids dub) is a Ghoul who works for Marik Ishtar in Yu-Gi-Oh!.
Pandora the Conjurer was an world-famous professional stage magician and illusionist (namely, "the greatest illusionist and magician since Harry Houdini himself," as he put it). He had everything: money, fame, and was in love with his lovely assistant, Catherine (who was also his fiancée). But one of his escape tricks (which he had practiced many times) went badly wrong, injuring him and scarring his face. He fell into despair and drove Catherine away, never seeing her again afterwards.
Pandora then met Marik, who promised to return Catherine to him if he defeated Yugi. As a result, Pandora became one of his Ghouls.
In Battle City, Pandora trapped Yugi Muto in a duel in which buzzsaws would move closer to them whenever a duelist lost life points and cut the loser's legs off (in the 4Kids version, they were dark energy disks would move closer to them whenever a duelist lost life points and trap their souls in the Shadow Realm when their life points reached zero). He dueled using two Black Magicians who looked quite different from Yugi's own Black Magician. But Yugi defeated him anyway, and unlocked his shackles. Yami then saved Pandora from the buzzsaw before he could be cut (as Yugi believed that not even Pandora deserved to be amputated). Marik then spoke through Pandora to Yugi.
Pandora the Conjurer appears as a boss in the video game, Yu-gi-oh! The Falsebound Kingdom. He appears as a minion of Scott Irvine, rather than Marik Ishtar. You fight him on the level "Lost Cause" in the Yugi Campaign in the Anker-Hill region. He uses his version of the Black Magician and two Dark Sleep-Inviting Lucifers. He would send seven soldiers to Yugi's party which consists of magic and dark monsters. After they are defeated, the player, preferably Yugi can fight him. Once defeated, Scott deletes Pandora's programming and when defeated for the first time, Black Magician #2 joins the list of monsters.