Unstable Underworlds plugin

This plugin allowed 1.21.11 paper servers to have the famous unstable SMP underworld region. To enter it you need to mine down in the nether and to leave you find the scattered portals around the underworld. An upcoming update add's custom structures and a custom Underworld farlands biome for players to explore it starts at 50k and will be customisable in the plugins config file. You will also have the option to FULLY turn them off.