Changes

In the first series anime, [[Shadi]] entered Yugi's mind room belonging to [[Yami Yugi|Dark Yugi]], looking for the secret powers of the Millennium Puzzle. Dark Yugi confronted him and challenged him to a game, where he was to find the true mind room amongst the countless mazes of doors that were riddled with traps. He failed, and was very nearly killed by a particular trap which caused the floor of the room to collapse. Dark Yugi saved him and Shadi left, defeated. A similar event happens in the second series anime during the [[Duelist Kingdom]] arc, but it is [[Yugi]] who rescues Shadi, not [[Yami Yugi]]. Yami Yugi also explains to Shadi that the Millennium Puzzle holds the power of unity, just as the many pieces of the Millennium Puzzle assembled and united.

It is able to initiate [[Shadow Game]]s and corresponding [[Penalty Game]]s that Dark Yugi used to punish those who harmed Yugi or his friends. In the Memory World arc, Atem couldn't summon the Egyptian Gods without the immense power of the puzzle. It can cast illusions, and can manipulate the minds and souls of others, such as when Yami Bakura put Bakura's soul inside of "[[Change of Heart (anime)|Change of Heart]]" but Yami Yugi changed it to Yami Bakura's soul in the card. It can even interfere with the magic of other Millennium Items, and at its full power. It can repelled the dark Seal of Orichalcos.