This nobody, Xsarc, was the nobody of Scar. He is cold, intellectual, deadpan snarky, and above all, very powerful. These traits were retained from the original Scar's personality. Xsarc knows that he desires revenge on Simba, but understands that he is needed for Xehanort's plans and so, he bides his time until he can track down the lion king...and order his execution personally. however, he was then robbed of this when Xehanort disires a much better member (which would later be Pitch Black.), thanks to the fact that Xsarc began to lose focus of the Union's true intentions
Xsarc will first appear in Spirited Away as a temporary member of the True Organization until Xehanort can replace him with another incarnation of himself. then he will be murdered by Oogie Boogie's Nobody for threatening betrayal and for Xehanort to presevre his wicked plans... or so it seemed. Turns out, apawn the nobody's defeat, he was able to escape to the pridelands in darkness, and battled against Scar's Heartless as part of it's own plan to go after Xehanort and his followers first, and then Simba. The heroes used this conflict to their advantage, and both were defeated. Xsarc fell first, angerly screaming he didn't get the revenge he deserved, finally silenced before Scar returned to normal.