Ansem, Seeker of Darkness or, alternatively, Xehanort's Heartless is the primary antagonist of Kingdom Hearts. A being of immense magical power, he seeks to drain the power of Kingdom Hearts, allegedly the origin of all darkness. A master manipulator and magician, he indirectly controls all the primary Disney villains throughout the first Kingdom Hearts game. He is also a member of the real Organization XIII, a group of Seekers of Darkness, comprised by thirteen incarnations of Master Xehanort, seeking to reforge the χ-blade and unlock the Kingdom Hearts to remake the world.
He has been featured in a number of spin-off tournaments, most notably the second Disney Villains War, the third Disney Vs Non Disney Villains war, and the second Disney Heroes vs. Villains and Heroes vs. Villains wars.