Echo Zane

Echo Zane is a Nindroid built using Zane's blueprint. He appearance is similar to Zane, except he is rustier and instead of Zane's core he has a wind-up power source. He seems to be less intelligent than Zane, although his senses in loyalty and friendship are no less than his titanium-shelled sibling.

History
After being imprisoned in the Lighthouse Prison, Dr. Julien, in his loneliness, sought to make himself company through the creation of the Tea Robot and Echo Zane, the latter of whom was a dead ringer for his first son, Zane. However, Echo Zane was faulty and was eventually sent to the basement prior to the Ninjas' arrival to the Lighthouse Prison and was left behind afterwards, presumably forgotten by his creator.

Echo Zane would eventually leave the basement, often roaming around the Lighthouse Prison with the Tea Robot as his friend, usually repairing himself with the help of his friend.

The Last Resort
After Jay and Nya arrived in an attempt to hide from Nadakhan, Echo Zane spied on them, but was eventually noticed by Nya. Retreating back to the basement to hide, he was quickly exposed, only to make friends when Jay and Nya revealed a lack of hostility towards him. While playing around with the two, Echo Zane noticed Nadakhan and Clancee spying on them through a mirror using the power of the latter's wish and quickly shattered it.

In preparation for the incoming invasion from the Sky Pirates, Echo Zane helped prepare several traps for the incoming enemies. Later, during the attack, he confronted Clancee after the latter got pass the door trap, only to be cornered by two pirates. However, upon seeing Jay and Nya in danger, Echo Zane overpowered his enemies, casually knocking aside Doubloon before confronting Nadakhan. Before he could fight back, however, his damaged state caught up to him and he fell apart into several pieces, being abandoned alongside his friend afterwards.

Operation Land Ho!
With the help of the Tea Robot, Echo Zane managed to rebuild himself, and was rescued from the Lighthouse Prison by Jay, joining his team of replacement ninja. Meeting in New Ninjago City, Echo Zane quickly detected Bucko and Sqiffy, and with the rest of the team succeeded in arresting Sqiffy before hitching a ride on a rising piece of land. Connecting to the rebuilt Djinjago, Echo Zane and the rest of the team managed to retrieve the Djinn Blade and took refuge in a nearby shed. Tasked with absorbing Jay into the Sword of Souls, Echo Zane accidentally mistook his signal "Go" under the wrong context, striking him down. After fending off Bucko and several other Sky Pirates, he reconciled with the freed Ninja and his brother Zane, the two delighted on the revelation that they had a sibling.

The Way Back
In order to protect the citizens from the falling chunks of Djinjago, Echo Zane and the rest of the ninja replacements headed back down to New Ninjago City alongside Sensei Wu and Misako, and later witnessed the realm's deconstruction.

As a result of Jay's final wish erasing the events of the season, Echo Zane was placed back in the Lighthouse Prison, presumably with no memory of the events that had happened.

Trivia

 * It is unknown why he bears a strong resemblance to Zane's Titanium Ninja form, since Dr. Julien passed away long before Zane assumed the role. This could be due to the his limited supplies and materials to build him, as was not the case with Zane, and also the fact that Echo *Zane does not have much shell coverings.
 * Despite his decrepit state, Echo Zane does have some ninja-like abilities programmed into him. One prominent ability is scaling up and staying on walls and ceilings.
 * Since his debut, Ninjago's Nindroid faction now has four eye-colors: the Overlord and Nindroids version are red; Echo Zane is yellow; P.I.X.A.L. is green; and the original Zane is blue.