Shen Lun was the great-grandfather of Frank Zhang, and the grandfather to Emily Zhang. They were all Roman demigods, with the blood of Poseidon. Shen Lun was the first ever heard of from the Zhang's to go to Camp Jupiter and join the legion. He is a legacy of Neptune, as Frank, Emily and Grandmother Zhang are as well. It was thought that he had caused the 1906 San Francisco, California earthquake, because he was a legacy of Neptune, but his name was later cleared by Frank in The Son of Neptune. Shen had been banished from the camp, wrongly, after the disaster had occurred.
Shen Lun was allowed into Camp Jupiter, because he was a very powerful demigod, that could help the legion. He wasn't very popular because of his Asian looks, his relation to Neptune (Poseidon in Greek form, which he was actually linked to) , and his shapeshifting ability, even though he had Roman ancestry in his lineage.
After the earthquake of 1906, Shen Lun was accused of causing it, as he was a legacy of the god of earthquakes, Poseidon. Shen denied causing it, but the Romans needed someone to blame. Despite Shen not having that kind of ability and with no evidence that he had caused it, Shen was banished for eternity from Camp Jupiter and New Rome .
Before Frank leaves for Camp Jupiter , his grandma gives him a note with an apology for what Shen Lun had done (but not really), and tells Frank to give it to the praetor of the camp. Reyna is the one who Frank apologizes to, but she orders him to not mention this to anyone.
After Frank manages to help save the camp from the giant army, people begin to talk about reinstating Shen Lun posthumously back into the Legion as there was no evidence to back up the claim that he had caused the earthquake of 1906 anyways.
- Shapeshifting- He had the ability to turn into any living or mythical animal, as all of the Zhang family can.