Sandyar Trek was a former Jedi Apprentice of Tahn Ya, who fell to the dark side and became Darth Krodhin. He was born on Shyyar, a desolate planet in the outer rims, and crashed on Kashyyyk. In 22 BBY, Sandyar was found by Tahn Ya on a surveillance mission in the Clone Wars. Tahn Ya sensed that the boy had great potential and was impressed by engineering prowess, so he took him in as his first apprentice. Sandyar learned from his master, and fought alongside him in many battles.