Board Thread:Theories and Rumors/@comment-26542216-20160116041949/@comment-27747281-20160214031414

I think Knighton and Clutch Powers' world are the most likely candidates for being realms. In Nexo Knights' third episode, while scrolling through hologram battlefields inside the Fortrex, you can see one for the Chi Temple, which indicates Knighton has a connection with Chima, which has a connection with Ninjago, which gives the reasonable assumption that Knighton is a realm.

As for Clutch Powers' world, it's more or less confirmed that Clutch Powers did visit Ninjago, and given how the rules of Clutch's world work a lot differently (namely how people have Creation sparks, being able to pull themselves apart, the presence of Lego bricks), I think it's safe to say that Clutch Powers' world is a separate realm from Ninjago.

And on an unrelated note, for Ultra Agents, I kind of doubt it. Although it's possible Tox and Paleman turned good, there's not really anything in the theme to indicate it is its own separate realm, as the setting could easily fit inside some obscure city in Ninjago.