Invisabat was discovered by Larry in the final episode when Larry when into the old barn located in Perfection. Larry went into it, and when he was observing mice, the bat flew down and hit Larry in the head, leaving a bruise. He tried to tell Rosalita, Nancy, and Jodi, but they didn't believe him. Later he went back to the barn with a fishing pole and hot dogs hoping he can catch the bat, as a pet. Near the end Delores came into the barn with Frank and El Blanco, Tyler and Rosalita tied up. The bat attacks Delores, causing her shotgun to go off, waking up El Blanco, and he eats her. Frank runs off, but is picked up and presumably shot by the accountant/hitman. Noted for being the only surviving mixmaster creation shown. It is not known what was "mixed" to create the bat or even what species of bat it is, though Larry compares it to a hummingbird. It is last seen following Larry outside the barn after he finds the key.
It should be noted that the invisibat is the only mixmaster mutation in the series to not pose a direct threat to the people living in Perfection. Mainly it just keeps to itself & swoops down after small rodents, except for the odd nonlethal attack on humans.