The Sixteen Realms

The Sixteen Realms are the worlds and dimensions parallel to Ninjago, which could formerly have been transferred via the Realm Crystal, an artifact that was located in the Tomb of the First Spinjitzu Master, but was destroyed by Flintlocke. Following the apparent destruction of the Cursed Realm after The Preeminent was destroyed, along with the destruction of Djinjago following the destruction of the Cursed Realm, there are currently only fourteen realms including Ninjago.

Ninjago Realm Group

 * Underworld
 * Ninjago (world)

Cloud Kingdom/Dark Realm Group

 * Cloud Kingdom
 * Dark Realm

Cursed Realm/Djinjago Realm Group

 * Cursed Realm/The Preeminent (Now destroyed)
 * Djinjago  (Destroyed due to the destruction of the  Cursed Realm ).

Miscellaneous

 * Chima

9 Other Unknown Realms

Trivia

 * The concept of the Sixteen Realms is similar to the Multiverse concept in various other fantasy and science fiction franchises. Notably, the fact that Chima is one of these worlds indicates that the Ninjago and Chima franchises share a Multiverse, though whether worlds based on other LEGO properties are also present is unknown.
 * Following their defeat at the hands of Captain Soto and his crew, the Sky Pirates were separated into various different realms, several if not most of which have not been featured or named in the series before.
 * Consequently destroying a realm could destroy its sister counterpart.
 * Realm groups are made up of two realms. the two realms that compose a given realm group, are opposite to each other. For example, Djinjago is beautiful, while the Cursed Realm is vile and decaying. Another example would be that the Cloud Kingdom is very bright, while the Dark Realm is very dark and lacks light.