Timed Wither Storm

A datapack stops the Wither Storm from spawning in its normal place and instead schedules it to appear once a chosen amount of game time has passed. The timer counts from a fixed point in the world, so the spawn moment is the same for every player on a server. Operators can change the timer length, pause it, or reset it with a trigger command, and a WitherStormControls trigger gives creative mode to an operator.

The mod depends on Cracker's Wither Storm Mod, which provides the Wither Storm itself, so that mod must be installed alongside it. Timed Wither Storm runs on the server, and players can join without installing it. Files exist for Forge and NeoForge, across six game versions 1.16.5 – 1.20.1, and the mod is released under the MIT License without being open source.