Before the story of the original Borderlands, T.K. Baha and his wife were attacked by Scar. In the end, Scar killed T.K. Baha's wife. When T.K. went to get revenge, Scar blinded him and stole his leg. When T.K. got a prosthetic leg from Dr. Zed, Scar stole that leg too.
Scar must be killed to obtain T.K.'s missing prosthetic leg and complete the mission, T.K.'s Life And Limb.
Scar drops drops level 1 or level 4 elemental artifacts depending on the playthrough and character level. He also drops level 6 artifacts after Playthrough 2 has been completed.
Scar has a chance to drop T.K's Wave after T.K.'s Life And Limb has been turned in.
The feud between T.K. Baha and Scar is a reference to the relationship between Captain Ahab and the Great White Whale, Moby Dick. Scar has swords sticking out of his body in the same fashion that Moby Dick is described as having harpoons sticking out of its body. "Baha" is "Ahab" spelled backwards. Also, Baha has one prosthetic leg, as does Captain Ahab.
As seen in the photo, before scar is killed, he only has three legs. Upon his death, he somehow has regained all four.
The sword that is embedded to his face is similar to Mordecai's while the knife in his side is similar to Roland's.
If Scar dies from corrosive disintegration the sword and a buzz axe will fall to the ground and remain.
Scar also is responsible for eating T.K. Baha's wife, in addition to T.K.'s leg and blinding him.