The Troll

The Troll was a huge green Cave Troll from Moria who was used by the Orcs in an attempt to enter Balin's Tomb.

Balin's Tomb
After Boromir closes the door to Balin's Tomb, a Troll attempts to enter by pushing the door. When the warrior attempts to fend it off, he is hit and falls back. Frodo Baggins uses his dagger and stabs it in its foot. The wounded creature flees in terror, screaming in pain.

Trivia

 * In Ralph Bakshi's The Lord of the Rings, the Troll is a giant green-like reptile creature covered in scales and after being wounded never appears again unlike the novels in which it and a few other cave trolls later appear throwing rocks at the Fellowship.