(Covers information from Anderson's universe)
In Resident Evil: Extinction, a new species of artificially-created Undead was introduced. These undead are unofficially called Super Undead. They were supposed to be domesticated by injecting a serum with Alice's blood, which did work, until the undead found a problem which it could not solve, causing a more primitive violence and anger, reverting it back to its (though vastly faster and stronger) original undead state. A batch of these undead were then made and shipped to Las Vegas (the convoy's destination). The convoy found the crate and released the batch of Super Undead, killing and reducing much more members of the convoy. This was also accomplished when Alice was controlled by Umbrella for a short time, enough for the Super Undead to eliminate remaining members before being killed by her and biting Alexander Isaacs, the one who originally made them.
Las Plagas UndeadEdit
In Afterlife, another variant of undead was introduced in the trailers which mirrored Las Plagas. These undead variant are not truly infected by the Plagas, instead the Plaga-like growth they had are stated as a new T-Virus mutation.