Shun is a ninja of Imagination. His family members were all masters of Imagination Spinjitzu, except for Shun and his brother, Runo. When he was a small boy, his villiage was attacked by skeletons, and he was the only survivor, or so he thought. He wandered for a long time, until he wandered into a small town. He ran into an old man, and when the man left, he followed him. He came to a monestary on top of a large mountain, where he found the old man and another boy sitting inside, eating rice. The old man spotted him, and told him to sit down with them. This man, known as Wu, would become his teacher of spinjitzu, and the boy, Zang, would become his best friend.
Later, Shun finds out that his brother is still alive,(from Lord Garmadon in disguise) he goes on a mission to rescue him, dispite Sensei Wu's advice not to, and falls victim to Lord Garmadons trap. When he wakes, he finds out that his brother Runo is still alive, but has been brainwashed into becoming Garmadons minion, and now weilds the powers of Chaos Spinjitzu. Garmadon is about to kill Shun, because he believes him to be a threat, but Zang arrives just in time and rescues Shun. They escape on Zangs pet dragon, but Runo manages to catch up to them, and after a battle on top of the dragon, Runo knocks Shun to the ground, and almost kills him, but Zang attacks Runo from behind, and knocks him off the dragon, supposedly killing him. They returned to the monastery, where they continued learning spinjitzu tactics and tricks.