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Custom Rules Editor

Design Your Own Universe

⚙️ What Are Custom Rules?

Conway's Game of Life uses specific rules (birth on 3 neighbors, survive on 2-3) that create its famous emergent patterns. But these are just one set of rules among thousands of possible "Life-like" cellular automata.

The Custom Rules Editor lets you modify these fundamental rules, creating entirely new universes with different behavior—from explosive chaos to crystalline stillness.

📐 Understanding B/S Notation

Life-like automata are described using B/S notation (Birth/Survival), which specifies how cells change based on their neighbor count.

B3/S23
Conway's Game of Life
B3
Birth on exactly 3 neighbors
S23
Survive on 2 or 3 neighbors

How Neighbors Work

Each cell has 8 neighbors (including diagonals). The rules check this count to decide what happens:

1
2
3
4
C
5
6
7
8
  • Birth (B): A dead cell with this many alive neighbors becomes alive
  • Survival (S): A living cell with this many alive neighbors stays alive
  • Any other condition: the cell dies or stays dead

🎛️ Using the Editor

The Rules Editor appears in the control panel. Here's how it works:

Birth
0 1 2 3 4 5 6 7 8
Survive
0 1 2 3 4 5 6 7 8

Click any number to toggle it on/off. Active numbers glow green. The current ruleset is always displayed in B/S notation at the top.

⚠️
Custom rules disable leaderboard eligibility to keep competition fair. Reset to B3/S23 for leaderboard play.

💡 Pro Tip

Rules are locked while the simulation is running. Pause or stop the simulation to modify rules.

🌟 Famous Rulesets to Try

Researchers have discovered many interesting Life-like automata over the decades. Here are some classics to experiment with:

B3/S23
Conway's Life
The original. Balanced between chaos and order. Has gliders, oscillators, and guns.
Classic
B36/S23
HighLife
Like Life but with a replicator! Small patterns can duplicate themselves indefinitely.
Has Replicators
B3678/S34678
Day & Night
Symmetric rule where patterns look the same inverted. Creates organic blobs.
Symmetric
B3/S12345
Maze
Creates labyrinth-like structures. Great for generating random mazes.
Maze Generator
B3/S45678
Coral
Grows organic, coral-like structures. Very stable growth patterns.
Organic
B36/S125
2x2
Creates patterns dominated by 2×2 blocks. Unusual crystalline appearance.
Geometric
B35678/S5678
Diamoeba
Creates large, amoeba-like organisms that slowly shift and merge.
Amoeba-like
B3/S238
Pedestrian Life
Similar to Life but with some patterns that move in unusual ways.
Life Variant

⚡ Quick Tips for Rule Design

Creating Stable Rules

  • Birth on 0 or 1: Causes explosive, instant fill—avoid unless you want chaos
  • No survival rules: Everything dies immediately—not useful
  • Survival on 8: Requires all neighbors alive—very rare condition
  • Birth = Survival overlap: Often creates more stable, interesting behavior

Behavior Patterns

  • Few birth conditions + many survival: Slow, stable growth (like Coral)
  • Many birth conditions + few survival: Explosive, chaotic behavior
  • Symmetric rules (B=S): Often create interesting reversible patterns
  • Adding B6 to Life: Enables replicators (HighLife)

🔬 Custom Rules vs Evolution Mode

Both features let you explore beyond standard Conway's rules, but they work differently:

  • Custom Rules: You manually set the rules before running. Rules stay fixed during simulation.
  • Evolution Mode: Rules automatically mutate during simulation based on fitness scoring. Creates a meta-evolution effect.

You can combine them! Set a custom starting ruleset, then enable Evolution Mode to see how it mutates from there.

⚙️ Create Your Rules

Ready to design your own cellular universe? Open the simulator and start experimenting with the Rules Editor.

Open Rules Editor →