Lua sandbox

Enabled mods can change your world and inventories. They must not get operating-system power (files, processes, or arbitrary system libraries).

Allowed

• Hooks on your script table (initialize, hitBlock, use, …)
• World helpers (spawn, query tiles, explosions, time, …)
• Utils helpers
• Documented proxies: self.item, self.armor, self.player, self.creature, structure / flora / projectile proxies
• require of scripts under Content/Lua, the base game’s content scripts, and your pack

Banned

Pattern	Why
io.*, os.*, debug	Host filesystem / process / debug
import(...), luanet, LoadCLRPackage	Bypass into the full game runtime
dofile / unrestricted loadfile	Load code outside the allowed folders
package.loadlib	Native libraries
World.Map	Raw map object — use World: helpers
.Underlying	Escape hatch into the full game object — sealed

Mod Prep Validate flags many of these as errors before you publish. The game also blocks them at runtime. There is no “trusted mod” escape hatch.

Still powerful

Sandboxing stops host compromise. It does not stop a script from spawning items, dealing damage, or exploding terrain — those APIs exist so gameplay mods can work. Only enable packs you trust with your saves.