The guardian is a blind old man who guards the Treasure of the Blind Swordsman.
When the Xiaolin Monks arrive at the cave to retrieve the treasure, they are confronted by the guardian. In order to claim the treasure, the guardian challenges them to beat him within five moves. Omi is initially reluctant to fight him as he is blind, but the guardian quickly proves himself a capable fighter. Omi eventually beats him with the "Look Behind You" trick, which the admitted to be the oldest trick in the book.
After this, the monks decide to take the guardian out of the cave with them, but they are confronted by Jack and Wuya, who kidnap the guardian and the monks' Shen Gong Wu. The monks go to rescue him, but ultimately, the guardian fights Jack and Wuya in a Xiaolin Showdown, beating both of them easily. 
The guardian usually acts as a wise old man, and takes his duty as the guardian of the treasure seriously. However, due to the fact that he is blind, he has a tendency to miss things, causing him to often look away from somebody he's speaking to, or attack where nobody is.
He's also ignorant of the fact that he lives in a cave.
The guardian is an old man, wearing a robe. He wears dark glasses over his eyes. He carries a cane, which he also uses as his main weapon.
Powers and Weaknesses
The guardian is blind, and has a tendency to miss things. This also means he can be easily fooled, as evidenced by the fact that Omi managed to him by telling him to look the other way. However, while his blindness usually appears to be a weakness, it does not hold him back, as he can sense his opponents with his mind.