Bug

A  (バグ, Bagu) is a singularity; an error, flaw, failure or fault in a computer program or system that causes it to produce undesired results. "Chaosmon" is the codename for Digimon who "should not exist", and according to the "" of the Digital World, are absolute impossible singularities.
 * Chaosmon
 * Chaosmon Valdur Arm
 * Ultimate Chaosmon