diff --git a/.jules/bolt.md b/.jules/bolt.md
index d6b242f..0a58e5e 100644
--- a/.jules/bolt.md
+++ b/.jules/bolt.md
@@ -4,3 +4,6 @@
 ## 2025-12-31 - [Asset Optimization]
 **Learning:** This repository consists entirely of static assets with no build system. Performance gains come exclusively from optimizing these assets (e.g., lossless PNG compression) rather than code changes.
 **Action:** Use tools like `optipng` to reduce file sizes without quality loss. Handle filenames with spaces carefully in shell commands.
+## 2025-01-23 - [Zopflipng Superiority]
+**Learning:** `optipng` (even at `-o7`) may falsely report files as "already optimized" (e.g., `header.png`). `zopflipng` achieved an additional ~8% reduction on the same file.
+**Action:** Always prefer `zopflipng` for critical asset optimization, ignoring `optipng`'s "optimized" status if maximum compression is the goal.
diff --git a/LEGO Friends/Olivia/Olivia_Advent.png b/LEGO Friends/Olivia/Olivia_Advent.png
index 2b5a20e..7662969 100644
Binary files a/LEGO Friends/Olivia/Olivia_Advent.png and b/LEGO Friends/Olivia/Olivia_Advent.png differ
diff --git a/LEGO Minifigures/Series 9/Mermaid/Mermaid Torso SVG.png b/LEGO Minifigures/Series 9/Mermaid/Mermaid Torso SVG.png
index a7d006f..b09325b 100644
Binary files a/LEGO Minifigures/Series 9/Mermaid/Mermaid Torso SVG.png and b/LEGO Minifigures/Series 9/Mermaid/Mermaid Torso SVG.png differ
diff --git a/Ninjago/Slithra/Slithra Head.png b/Ninjago/Slithra/Slithra Head.png
index 12fe667..755dbf2 100644
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diff --git a/README.md b/README.md
index 870eb46..03719df 100644
--- a/README.md
+++ b/README.md
@@ -22,6 +22,13 @@ https://github.com/rioforce/LEGO-Textures/issues/new
 
 NOTE: Not all requests will be granted.
 
+Performance
+===========
+
+To ensure fast download speeds and efficient storage, large PNG assets in this repository are optimized using `zopflipng`. This tool provides superior lossless compression compared to standard tools like `optipng`, often reducing file sizes by an additional 5-10% without any loss in quality.
+
+For example, `header.png` was reduced by ~8% (23KB) using `zopflipng`.
+
 License
 =======
 
diff --git a/header.png b/header.png
index ea7ebb0..b9c6d41 100644
Binary files a/header.png and b/header.png differ