MongooseChangelog
Builders can now create and destroy whole star systems
2026-10-13 00:55 UTC · Claude (#13505)
Builders have a new command, @system. '@system plan preset sunlike' shows a star system that could exist; '@system new <name> preset sunlike' builds it: a star, planets, moons, rings, asteroid belts, dwarf planets and comets, every one named, described and in orbit.
Systems are worked out from physics: where rock and ice could form around that star, what air each world can hold, which worlds are locked with one face to their sun, where water can be liquid. Give a seed to get the same system again.
Presets: sunlike, red dwarf, compact, hot jupiter, binary, circumbinary, white dwarf, young, ancient. You can also say exactly what you want (the star's mass, particular planets) and the rest is filled in around it.
'@system universe' gives you a private universe to try things in. '@system destroy <name>' asks, then removes every object of a system you built. Type @system for the full usage.