Mob Spawn Indicator

Mob Spawn Indicator highlights valid mob spawn floors in your vicinity with color-coded overlays. It uses vanilla spawn rules, so it works on any server without needing to be installed server-side.

Features

• Color-coded overlays on valid spawn floors: red (danger), yellow (warn), green (safe)
• Configurable render distance, opacity, and which colors to display
• Settings GUI accessible from the Options screen or via commands
• Client-side only — works on vanilla servers, SMPs, and modded servers

Commands

• /msi settings — open the settings GUI
• /msi toggle — toggle the overlay on/off
• /msi on | /msi off — enable or disable the overlay
• /msi reset — reset all settings to defaults

Configuration

Default keybind: J (toggle overlay)

Config file: config/msi-common.toml

| Option | Default | Description |
|—|—|—|
| render_rad | 16 | Render distance in blocks |
| overlay_opacity | 0.5 | Overlay transparency |
| show_danger | true | Show red overlay (valid spawn, no space for mobs) |
| show_warn | true | Show yellow overlay (valid spawn, 1 block space) |
| show_safe | false | Show green overlay (valid spawn, 2+ block space) |

Notes

• Uses vanilla Minecraft spawn rules: slabs, stairs, trapdoors, glass, and leaves are correctly excluded as non-spawnable
• Overlays update every 5 ticks
• Works in singleplayer, LAN, and multiplayer