EFM2 Atmosphere Client 0.1.2 is a client-side Fabric mod for Minecraft 1.21.3. It is designed for the Escape from Maniac 2 map/event and connects to the Paper/Leaf server plugin EFM2Companion 0.1.3 through its ModBridge protocol.
This mod does not replace the Paper plugin and does not replace Simple Voice Chat. The server remains authoritative for radio ownership, channel state, cooldowns, active time, private calls, roles, round state, maniac proximity, and voice status.
The client mod provides the visible atmosphere layer:
- radio HUD with the included radio icon;
- screen static and glitch overlays;
- radio channel menu;
- incoming private-call popup;
- client-side radio sounds;
- visual response to EFM2Companion server packets.
- Minecraft 1.21.3
- Fabric Loader
- Fabric API
- Fabric Language Kotlin
- Java 21
- EFM2Companion on the Paper/Leaf server for live radio state
Without EFM2Companion installed on the server, the mod stays quiet: no radio HUD is shown unless debug is enabled, keybinds show a small bridge-missing message, and the client does not spam packets.
With EFM2Companion installed, the client waits for SERVER_HELLO_S2C, sends HELLO_C2S, receives HELLO_ACK_S2C and state packets, renders HUD/effects, plays sounds, and sends radio requests back to the server. If the server hello does not arrive after a short delay, the client sends one fallback hello and then waits without spamming packets.
These are Fabric client commands, not server commands:
/efm2client status/efm2client test hud/efm2client test menu/efm2client test overlay static/efm2client test overlay maniac/efm2client test sound on/efm2client test sound off/efm2client test sound static/efm2client test sound warning/efm2client bridge hello/efm2client bridge request-state