Smyth is a machine cyborg. He was a member of the Night Stalkers before being enlisted by the Machines as their agent.
Injured while hunting Dominik, Smyth is turned by Rosa. He later wakes up but is in a bad way and begs to be put out of his misery. Rosa however refuses and tries to convince him to join her. He attempts to run off, though is shot on the way by Bernie.
He is later shown heading towards his old family home. Upon arrival he greets his family, reveals his new form, as the screen turns to red.
With scrufflebeck in tow, Smyth was approached by a Machine Scout and brings them in.
In 'A New Machine' Smyth is met by the Machine City's meditator and is transformed into a cyborg; effectively turning him into a zombie, vampire, human, machine hybrid.
However, his mind is transferred to one of the subjects, being held in their containment rooms, as a disguise and assigned to scope out the enemy's defenses, which is the Machine's target: New Hammerston, and using Rusty to help him find his way around.
Even with Joe against them, the Machines believe that with Smyth's combined abilities that can completely wipe out the human race and control the entire world.
With the combined abilities of a vampire, zombie and cyborg, it can be assumed that Smyth has more abilities than he would've as a vampire; with various abilities such as distintegration rays, lasers and superhuman strength; being able to bound even fortress walls with ease.
It is currently unknown if this is matched with the those of Bernie or Jessie's suits or those harboured by Joe and Rosa