nocware
Quick answer
- On Java 1.18+, hostile mobs only spawn where the block light level is 0.
- Any torch, lantern or other light near the floor stops mobs spawning there.
- Light drops by 1 for every block away from the source.
Creepers in your base? Zombies in your mine? It's all about light. Get this right and mobs can't spawn near you at all.
How bright is each light?
| Light | Light level |
|---|---|
   Lantern, glowstone, sea lantern, jack o'lantern | 15 |
| Torch | 14 |
  Soul torch, soul lantern | 10 |
Light goes down by 1 for each block you move away, counting each direction separately. A torch at 14 lights up roughly 13 blocks in a straight line before it hits 0.
What "light level 0" means
0block light needed for hostile mobs to spawn (Java 1.18+)
1+any block light at all keeps them away
So you don't need a torch every few blocks any more. You just need every floor block to get some light.
Check with F3On Java, the debug screen (F3) shows the block light level where you're standing. Walk around your base and look for 0s.
Lighting a big area
- Place lights in a grid. With torches, about every 12 to 13 blocks keeps the gaps lit.
- Light under overhangs and inside every room, not just outside.
- Check dark corners and the tops of walls and roofs: mobs spawn there too.
Light doesn't stop everythingSpawners, slimes, and mobs walking in from the dark can still reach you. Light only stops new mobs spawning on the lit blocks.
Hardcore must-doLight up your base fully before your first night. Most early Hardcore deaths come from a creeper that spawned somewhere you thought was safe.
Cheat sheet
- Hostile mobs need block light 0 (Java 1.18+)
- Torch 14, lantern 15, soul torch 10
- Light drops 1 per block
- Lights every ~12 blocks covers the gaps
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