THE LEGEND MOD PROJECT
EXPANDING LAND FFA SERVER
The World's Largest IO Game Arena • 1024 Concurrent Players • Written in Pure C

What is this?

A high-performance FFA server built entirely in C from the ground up. Zero GC pauses, pre-allocated memory pools, split quadtree optimization — designed for authentic Agar.io mechanics with blazing speed.

This is the only IO game server in the world capable of handling 1024 concurrent players per arena — with the architecture to scale even further in the future.

📍 Server location: Nuremberg, Germany (Hetzner) — optimal latency for EU players.

🎮 Features

  • Full Agar.io protocol — leaderboard, ghost cells, skins, names, chat, spectate
  • Real anti-teaming — authentic Agar.io decay mechanics (see below)
  • Anti-cheat scramble — coordinate scrambling per player
  • Session stats — time alive, highest mass, food/players eaten on death
  • WSS/TLS encrypted — secure WebSocket connections
  • 1024 player capacity — the largest IO game arena in the world, ~5 ms tick time vs ~40 ms on Node.js servers

🛡️ Anti-Teaming System — Exponential Decay

This server uses an exponential multiplier-based anti-teaming system (ported from the Delta Server architecture). Each player has a single extra decay multiplier — teaming actions increase it, time naturally decreases it. No event arrays, no thresholds — just a smooth, continuous curve.

How It Works

Every decay cycle (every 4 seconds), your effective decay is calculated as:

effective decay = base decay × pow(1.086, multiplier)

When your multiplier is 0, your decay is exactly the base rate (−0.8%/4s). As the multiplier grows, decay increases exponentially — light play barely notices, but heavy teamers get punished fast.

Multiplier Bumps

These actions increase your multiplier:

  • ◉➚◉ Split+0.5 per split action
  • ⬤ W (eject mass)+0.1 per W press (flat, not per cell)
  • ☣ Virus (pop)+0.5 per virus consumed
  • ⚠ Danger Zone+0.01 per decay cycle while in the outer ring during map contraction

Natural Recovery

Every decay cycle, the multiplier decreases by 0.005 (the compensation constant). This means your multiplier naturally cools down during normal play. If you stop teaming, your decay returns to normal — no waiting for event timers to expire.

Decay Examples

Multiplier Decay Rate What It Means
0 (clean) 1.00× base (0.8%/4s) Normal play
1 1.09× base Barely noticeable
5 1.51× base Moderate teaming
10 2.28× base Heavy teaming
20 5.19× base Extreme — mass melts

∞ Constant Decay

The base decay is always active: −0.8%/4s (vanilla Agar.io rate, verified from 97,806 real packets). A 10,000 mass cell loses ~80, a 100 mass cell loses ~0.8. This rate is the same regardless of how many players are in the arena.

Live Stats HUD

When connected to Expanding Land FFA, the stats bar shows your current multiplier and effective decay rate. Multiplier = 0 means you're clean. The higher the number, the more extra decay you're taking.

📊 Enable / Disable the Display

The decay stats are enabled by default in Legend Mod. To toggle them:

  1. Open Settings (gear icon)
  2. Find the Stats section
  3. Toggle "Decay Info (Expanding Land)" on or off

This setting only affects Expanding Land FFA. It has no effect on other servers.

⚙️ Current Tuning Values

These are the values we currently use. We need your feedback to get them right!

Tick rate: 25 ticks/secnon-negotiable, verified from real Agar.io.

Setting Value Description
at_extra_decay_base 1.086 Exponential curve steepness
at_compensation 0.005 Multiplier recovery per decay cycle
at_split_loss 0.5 Multiplier bump per split
at_eject_loss 0.1 Multiplier bump per W press
at_virus_pop_loss 0.5 Multiplier bump per virus pop
at_danger_loss 0.01 Multiplier bump per danger zone cycle
player_decay_rate 0.002 (0.8%/4s) Base decay rate

🎯 We Need YOUR Help to Tune These Numbers!

The anti-teaming system uses Delta Server's exponential curve and we need the community's input to fine-tune the values. Does the multiplier grow too fast? Too slow? Is recovery too quick? Your gameplay experience is crucial.

Watch your multiplier in the stats bar and tell us what you think:

💬 Join our Discord & share your feedback

Tell us your multiplier numbers (e.g., "after 10 splits my multiplier was 5.0 and it felt too harsh"). Screenshots of your stats display are very helpful!

🚀 How to Play (Legend Mod)

  1. Select region Private
  2. Choose 👑 Expanding Land FFA (it's the default!)
  3. Click Play and enjoy!

Delta users: Update the addon for full support:
Install Delta · Get Legend Addon

🌐 Other Mods / Custom Clients

You can connect from any Agar.io mod or custom client using this server address:

wss://ffa.legendmod.ml:8080

Paste this URL into your mod's server/WebSocket field and play. Works with OGARio, Delta, Agar2, and any OgarII-compatible client.

📱 Expanding Land — Android App

Want to play Expanding Land as a native Android app? Install it directly on your phone — no Play Store account needed. This is a standalone app that runs fullscreen without a browser.

⬇️ Download APK (ExpandingLand-v2.apk)

Android may ask you to allow installs from unknown sources — this is normal for apps distributed outside the Play Store. We distribute directly because we are an independent open-source project and prefer not to go through Google's paid developer verification process.

Legend Mod Community • legendmod.ml