1. A malware evaluator system, comprising: a non-transitory memory storing a variant of a malware specimen; and one or more hardware processors coupled to the non-transitory memory and configured to read instructions from the non-transitory memory to cause the system to perform operations comprising: scanning the variant with one or more malware detectors to determine an evasiveness characteristic of the variant and a maliciousness characteristic of the variant; determining a likelihood that the variant meets one or more criteria based at least on the evasiveness characteristic of the variant and the maliciousness characteristic of the variant; based on the determined likelihood, selecting the variant for mutation; and mutating the selected variant to generate one or more successive variants.