Clone Abby is a playable unit in Metal Slug Attack, first appearing in the Extra Ops "Double Face". Parts can be obtained through her Box Crank.
The Professor's version of Abigail, Clone Abby is essentially the same as her human counterpart; attacking from afar with lasers. It has more health and deals more damage, but has only two lasers (compared to four from Abigail) and lacks the high-powered close range attack. Clone Abby cannot pierce with its special, and lacks the debuffing effects Abigail has.