Looking for cool features for a skyblock server

[FrameworkGFX]

The title says it all really, I have the experience and development team to create almost anything. just drop it in the comments.

Here are some I already have:

- Custom challenges; not the same as every skyblock server ever.
- craftable spawners; crafted from custom items.
- bosses that can spawn on islands to add a little risk; good loot if killed

 

[Cleora]

I got some ideas but ideas are hard to come by and if successful could be worth a couple bucks.