XYZCRUSH

XYZCrush is a small tool to recompress RPG Maker 2000 and 2003 XYZ image files into smaller files.

How to use: drag and drop your XYZ files over the executable icon. You may drag multiple files.

It uses Zopfli to better compression ratios, but it is very slow while it compresses. Compressed files are still fully compatible with RPG Maker and EasyRPG while keeping fast reading (or even faster).