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Clones don't spawn - Troubleshooting clone creation issues in Scratch

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💡 Struggling with clone creation issues? Can’t figure out why your clones won’t spawn? 🚀 Get Debug Help Now

GA

GameDev_Alex

Posted on July 24, 2025 • Intermediate

🚫 Clones suddenly stopped spawning!

Hey everyone! I’m working on a game project and ran into a frustrating issue. My clone system was working perfectly, but after adding some new sprites and mechanics, the clones just stopped spawning entirely!

The problematic code looks like this:

when I start as a clone
create clone of [projectile]
delete this clone

What’s weird is that:

  • It worked fine initially with just one sprite
  • Problems started when I added multiple sprites creating clones
  • No error messages - clones just don’t appear
  • Same issue happened in my previous zombie shooter game

Has anyone encountered this before? Is there a clone limit I’m hitting? Any debugging tips would be amazing! 🤔

CD

CloneDebugger_Pro

Replied 15 minutes later • ⭐ Best Answer

@GameDev_Alex You’ve hit the classic clone limit issue! 🎯 Let me break down the most common clone spawning problems and their solutions:

🔍 Clone Problem Diagnosis Flow

flowchart TD A[🚫 Clones Not Spawning] --> B{Check Clone Count} B -->|> 300 clones| C[❌ Clone Limit Exceeded] B -->|< 300 clones| D{Check Broadcast Setup} C --> E[Delete Unused Clones] E --> F[Implement Clone Recycling] D -->|Clones receiving broadcast| G[❌ Clones Creating Clones] D -->|Only master sprite| H{Check Sprite Conditions} G --> I[Add Master Sprite Check] H -->|Conditions met| J{Check Script Execution} H -->|Conditions not met| K[❌ Logic Error] J -->|Scripts running| L[❌ Timing Issue] J -->|Scripts not running| M[❌ Broadcast Not Received] K --> N[Fix Conditional Logic] L --> O[Add Delays/Waits] M --> P[Check Broadcast Names] I --> Q[✅ Problem Solved] F --> Q N --> Q O --> Q P --> Q style A fill:#ffebee style C fill:#ffcdd2 style G fill:#ffcdd2 style K fill:#ffcdd2 style L fill:#ffcdd2 style M fill:#ffcdd2 style Q fill:#e8f5e8

🚨 Problem #1: The 300 Clone Limit

Scratch has a hard limit of 300 clones total. Here’s how to manage it:

    // Clone counter and cleanup system
when flag clicked
set [active clones v] to [0]
set [max clones v] to [280] // Leave buffer for safety

// Before creating any clone
define create clone safely (sprite name)
if <(active clones) < (max clones)> then
create clone of (sprite name)
change [active clones v] by (1)
else
// Handle clone limit reached
broadcast [cleanup old clones v]
wait (0.1) seconds
create clone of (sprite name)
change [active clones v] by (1)
end

// In each clone
when I start as a clone
set [my lifetime v] to [0]
forever
change [my lifetime v] by (1)
if <(my lifetime) > [300]> then // Auto-cleanup after 5 seconds
delete this clone
end
wait (1) seconds
end

// When clone is deleted
when I start as a clone
wait until <not <touching [edge v]?>>
change [active clones v] by (-1)
delete this clone

🎯 Problem #2: Clones Creating Clones

This is the most common issue! Clones receive broadcasts too:

    // WRONG - Clones will also create clones!
when I receive [spawn projectile v]
create clone of [projectile v]

// CORRECT - Only master sprite creates clones
when I receive [spawn projectile v]
if <(clone id) = [master]> then // or use another master check
create clone of [projectile v]
end

// Alternative method using sprite detection
when I receive [spawn projectile v]
if <(x position) = [0]> and <(y position) = [0]> then // Master sprite position
create clone of [projectile v]
end

// Best method - use dedicated master sprite
when I receive [spawn projectile v]
if <(costume name) = [master costume]> then
create clone of [projectile v]
end

🔧 Problem #3: Broadcast Timing Issues

Sometimes broadcasts don’t reach sprites properly:

    // Add debugging to track broadcasts
when I receive [spawn projectile v]
say [Received spawn broadcast!] for (1) seconds
if <(clone id) = [master]> then
say [Creating clone...] for (1) seconds
create clone of [projectile v]
say [Clone created!] for (1) seconds
end

// Alternative: Use direct clone creation
when [space v] key pressed
if <(clone id) = [master]> then
create clone of [projectile v]
end

// For complex timing, use wait blocks
when I receive [complex spawn v]
wait (0.1) seconds // Let other scripts finish
if <(clone id) = [master]> then
create clone of [projectile v]
end

🛠️ Problem #4: Clone Lifecycle Management

Proper clone management prevents issues:

    // Complete clone management system
when I start as a clone
set [clone id v] to (join [clone_] (timer))
set [clone active v] to [true]

// Main clone behavior
forever
if <(clone active) = [true]> then
// Your clone logic here
move (5) steps

// Check for cleanup conditions
if <touching [edge v]?> or <touching [enemy v]?> then
set [clone active v] to [false]
broadcast [clone destroyed v]
delete this clone
end
end
end

// Clone recycling system (advanced)
define recycle clone (new x) (new y) (new direction)
set [clone active v] to [true]
go to x: (new x) y: (new y)
point in direction (new direction)
set [clone lifetime v] to [0]
show

// Instead of deleting, recycle
define deactivate clone
set [clone active v] to [false]
hide
go to x: (-1000) y: (-1000) // Move offscreen
broadcast [clone available v]

🔍 Debugging Tools

Use these techniques to diagnose clone issues:

    // Clone counter display
when flag clicked
forever
set [clone count display v] to (join [Clones: ] (active clones))
wait (0.1) seconds
end

// Clone creation logger
define log clone creation (sprite name)
change [total clones created v] by (1)
say (join [Created clone #] (total clones created)) for (1) seconds

// Broadcast debugger
when I receive [any broadcast v]
say (join [Received: ] (broadcast name)) for (2) seconds

// Performance monitor
when flag clicked
forever
if <(active clones) > [250]> then
say [WARNING: High clone count!] for (2) seconds
set [performance warning v] to [true]
end
wait (1) seconds
end

💡 Best Practices

  • Always check if you’re the master sprite before creating clones
  • Implement clone limits to prevent hitting the 300 limit
  • Use clone recycling for frequently created/destroyed clones
  • Add debugging output to track clone creation
  • Clean up clones regularly when they’re no longer needed
  • Use “run without screen refresh” for clone management blocks

Your issue is most likely #2 - clones creating clones! Add a master sprite check and you should be good to go! 🎯

GA

GameDev_Alex

Replied 30 minutes later

@CloneDebugger_Pro THANK YOU! 🙌 You were absolutely right!

It turned out to be exactly problem #2 - my clones were receiving the broadcast and creating more clones. I added the master sprite check and everything works perfectly now!

    // My fixed code
when I receive [spawn projectile v]
if <(costume name) = [player_master]> then
create clone of [projectile v]
end

The debugging tips were super helpful too. I can now see exactly how many clones are active and catch issues before they break the game. This will save me so much time in future projects!

PO

PerformanceOptimizer_Sam

Replied 1 hour later

Great solution! 🎯 For anyone dealing with complex clone systems, here are some additional performance tips:

⚡ Advanced Clone Optimization

    // Object pooling for high-performance games
when flag clicked
set [pool size v] to [50]
repeat (pool size)
create clone of [projectile v]
end

// In projectile clone
when I start as a clone
set [in use v] to [false]
hide
go to x: (-1000) y: (-1000)

forever
if <(in use) = [false]> then
wait until <(in use) = [true]>
show
// Projectile behavior
repeat until <touching [edge v]?>
move (10) steps
end
set [in use v] to [false]
hide
go to x: (-1000) y: (-1000)
end
end

// To use a pooled projectile
define fire projectile (start x) (start y) (direction)
broadcast [request projectile v] and wait
if <(available projectile id) > [0]> then
broadcast (join [activate_] (available projectile id))
end

This approach reuses clones instead of constantly creating/deleting them, which is much more efficient for games with lots of projectiles! 🚀

VB

Vibelf_Community

Pinned Message • Moderator

🐛 Master Clone Debugging & Optimization

Excellent troubleshooting discussion! Clone management is crucial for complex Scratch projects. Need help with advanced debugging techniques or performance optimization? Our experts can guide you through:

  • 🔍 Advanced debugging and profiling techniques
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