After becoming promicin-positive himself due to being infected by a promicin-inducing virus in "The Great Leap Forward", Jed Garrity unconsciously creates a fully-clothed, self-aware duplicate of himself.
The copies that are created through this ability are completely identical to each other, so much so that neither is able to tell whom is the original. Other copies are only able to be created after one dies, doing so in a safer environment (Welcome to Promise City). When one of these copies does die, the other existing copy experiences the trauma but the replacement doesn't retain any instant knowledge of it.
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