Hostile mobs like zombies and creepers appear in the dark. This pack shows you exactly which blocks are dark enough, so you can light your base without guessing.
Finding the dark spots
1. Make sure the overlay is enabled in Options → Resource Packs.
2. Walk through your base at night, or with the area otherwise unlit, so you see the real lighting.
3. Check every floor, roof, balcony and corridor for blocks marked light level 0.
4. Don't skip corners, spaces behind furniture or the ground just outside your walls. Mobs often appear in these overlooked spots.
Placing torches efficiently
1. Stand in the middle of a cluster of light level 0 blocks and place a torch or other light source.
2. Watch the markings update. Blocks next to your new light should show 15.
3. Look for any remaining 0 blocks and place light near them.
4. Use the light level 1 markings to find the edge where light is fading. Placing your next torch near that edge connects the lit areas without wasting torches.
5. Repeat until no blocks marked 0 remain anywhere you want to keep safe.
Walk the whole base one more time at the end. A single forgotten dark patch is enough for a creeper to appear.