Pitbulls

From Tomb Raider Wiki

Pitbulls are among the three animal enemies you encounter in Tomb Raider: Legend. They are found in the Japan and England levels, along with some mercenaries backing them up, naturally. Also, they are never alone. There's always at least two pitbulls in one area.

The pitbulls can be quite a pain to dodge if you accidentally slip and fall onto the ground. They'll usually overpower you for a second or so, tripping you over 2 more times at most, before you can manage to jump away and finish them off.