Demon Teddy Bear

The demon Teddy Bear was first encountered in the episode "Change of Plans".

They are extremely fast, and can seemingly teleport. Despite them wanting to kill everything in sight, they are surprisingly ineffective at killing, as Will was attacked twice, still coming out of the brawl alive.

The Demon Teddy Bear's main attack strategy is possibly suffocating, or choking somebody, as when Will was attacked by the bears both times, he pulls them both off, breathing heavily, as if being choked, although this just may be from fear.

They cannot move if they are being looked at, or can be seen, similar to the weeping angels in Doctor Who, although in one scene, Will sees a teddy bear peeking from around the corner, quickly going back into hiding once it is spotted.

They have an ability to hack phones, as the blonde one disconnected the call between the Plumber and Will, and started speaking through it.

They may be scary, but besides choking people, moving quickly and hacking phones, there's not much more they can do. However, Alec Baker himself stated "The Teddy Bears will return soon, and when they do, they will be scarier, fiercer, and more dangerous than you've ever seen them before."

Alec Baker also stated that he is now terrified of the innocent teddy bears he used after this episode was filmed.