The spirits of the Cursed Realm appear to have elemental abilities to transform and possess objects and organisms. As ghosts they are immune to most forms of physical attack, but are vulnerable to water as it is ever changing, which can cause them to dissolve into ectoplasm. Their only other vulnerability is to Deepstone, a substance mined from beneath the ocean floor, which can either contain them or be forged into weapons for use against them, such as the Aeroblades the ninja obtain from Ronin. While Morro leads the group in the field, their true master is the Preeminent, Queen and embodiment of the Cursed Realm. The Sky Pirates are a motley crew of renegades who are led by Nadakhan, a Djinn from Kingdom of Djinjago. "LEGO Ninjago: Master of the 4th Dimension" is a 4D short film released at LEGOLAND on January 12, 2018. The Carlsbad theme park announced a new 3D/4D movie experience called "LEGO Ninjago: Master of the 4th Dimension" that was scheduled to open in the summer. Peter Ronchetti, general manager of LEGOLAND California, said "LEGO Ninjago: Master of the 4th Dimension" would open in all LEGOLAND theme parks around the world at the same time. Michael D. Black is the short's director, and the writer is Robert Henny. Producers are Joshua Wexler and Laura Jackloski. In 2009, LEGO proposed to make a series on ninja, deciding that there would be four ninja with elemental powers. Later, Tommy Andreasen and Thomas Fenger created the martial art of Spinjitzu. In the United States, two pilot episodes, later split into four episodes total, were shown on Cartoon Network on January 14, 2011. They were released in Europe on January 24, 2011. The pilot episodes focused on Kai as he goes from being a blacksmith to a Ninja to save his sister, Nya. Due to the popularity of the pilot episodes, the first season was launched from December 2011 – April 2012 alongside a new line of sets marketed as "Rise of the Snakes". The pilot episodes were released on DVD in March 2011, and the first season became available on DVD in Region 1 on June 26, 2012. The series as a whole has an estimated budget of kr 37 million (approximately £4.6 million or US$6.7 million). Due to the positive reception of the pilot, a full series was commissioned and began broadcast in December 2011.