Stranger Things: Number 23

Laura Kinney. Otherwise known as Number 23. Possibly Brenner's most prized possession. Having unbelievable regenerative capabilities, Laura is unkillable. In addition to that she can grow two large metal claws from both wrists and one on each foot. Once again, due to Brenner's experiments with a limited supply of metal he had called Adamantium, he had surgically removed Laura's claws and coated them in Adamantium before inserting them back in.

Laura was a project Brenner kept secret even from the other children. He could not allow her to have attachments, he could not allow her to get close to Eleven, Who knows what destruction those two would bring.