Proto-Nephilim

Introduced in Tomb Raider: Angel of Darkness, the Proto-Nephillim (or Black Angel if you're a zombie trucker guy) is the creation of Kristina Boaz. Half Nephillim, half biological experiment. It's a vicious dog-like creature that can only be killed by Periarpt Shards.

Eckhardt ordered Boaz to kill the beast, but she didn't. When Lara turned off the power to the Bio-Research Facility, the Proto got loose. After a chase through a hospital loaded with mutants and zombies, Kurtis Trent put the animal down via Periarpt Shards.