Dr . Julien Dr . Julien is a character of the Ninjago theme . He appeared as Zane ' s creator in the first season of " " . Although first assumed dead , he reappeared in the second season as he was revealed to be revived by Samukai just after his death . However , Cyrus Borg mentions that he died for good in the third season . Background . Father and Son . Dr . Julien is the inventor that built Zane and the Falcon . His origins are unknown , but he originally lived in a fortress built in Birchwood forest , guarded by a Juggernaut , built to defend to place against Treehorn s . He spent most of his life with his " son " and he taught Zane to do many everyday things . Although Zane was created from scrap parts , he was made with a unique power source , with is currently unknown . When he was on his death bed , he told Zane he was made to protect those who cannot protect themselves and that he needed to move on to the next stage in life . Before he passed away , he switched off Zane ' s memory switch so he could not hurt Zane with loss . Revival . In the next season , it is revealed that he is still alive and held captive in a deserted jail in the middle of a vast sea . It turns out that shortly after his death , Samukai visited him and revived him with a potion , forcing him to build powerful skeleton machines that would aid him in attacking Ninjago . To avoid him escaping , Samukai prisoned him on an island chained a large sea creature called Leviathan at the bottom of the sea as a guard . Due to Samukai ' s death , he was not freed and stayed in the prison for a long time . Last Voyage . In " The Last Voyage " he was meet with the Ninja and reunited with Zane . He then told them about his revival and imprisonment . He and the Ninja them fixed the broken " Destiny ' s Bounty " and escaped from the island . He has since aided and lived alongside them in the events leading to the final battle between Lloyd and the Overlord . Death . In the third season , it is revealed that he died from unknown reasons ( it is likely his age caught up with him ) , and Zane secretly mourns losing him again . Cyrus Borg comforts him in hinting that he and his father knew and worked together . In the end of the season , when Zane sacrificed himself to the Golden Master and was near his death , he remembered everything he did with his father , so Dr Julien appeared in flashbacks informing him to " protect those who cannot protect themselves . Echo Zane . It was later revealed that when Dr . Julien was trapped in the lighthouse , he had created a second Nindroid based on Zane ' s blueprints . However , he did not turn out to be as advanced as the original Zane . " Echo Zane " was discovered by Jay and Nya when they hid in the lighthouse from Nadakhan and his Misfortune ' s Crew . Wu ' s Vision . At the end of The Dark Island Trilogy , Sensei Wu had a vision of Dr . Julien , followed by visions of Sensei Yang , Ray and Maya , and Acronix and Krux . Day of the Departed . In Day of the Departed , Zane visits a statue of Dr . Julien located near his old lab in celebration of the holiday ; it is later shattered by General Cryptor , who refers to Julien as " our [ his and Zane ' s ] dad . "