[cuppajava]

Added a few months ago (I think?), there's a new world type called twisted league that should have a filter like .isTwistedLeague() in WorldOverview like .isPVP(), isDeadman() etc have.

A temporary workaround is

"Twisted League".equals(world.getActivity())

but it's still something that should be in the API for uniformity.

 

[savior]

There should be something like isSeasonal()

 

[cloud]

This is exposed as WorldOverview#isLeague()