Dr. Brewer's Clone

Dr. Brewer's Clone is a fictional character and antagonist from the children's book series of Goosebumps who was introduced in the 2nd book, Stay Out of the Basement and later its television adaption. He is a golem (or plant copy) of his original creator, Dr. Michael Brewer, a botanist who was working on a super-plant, trying to electronically make a new plant using DNA elements from other plants. While he was working on it, Dr. Brewer accidentally cut his hand on a slide where some of his blood had gotten mixed in with some of the plant molecules he was using, resulting in the clone's creation. The clone looked human, but he still had some plant flaws, making him imperfect. Despite these flaws, it gained the upper hand somehow and encased his creator within the basement closet to contain (and imprison) him whilst he continued his work, much to the suspicions of Dr. Brewer's children Margaret and Casey before he eventually became obsessed with wanting to expanding his environment in hopes of creating more clones, starting with Dr. Brewer's family.