Example of use:
[create image a.png and b.png]
[create texture.txa]:
:group main dir textures
:margin 0
*/*.egg : main

Execute:
egg-texture-cards -o cards/a.egg a.png
egg-texture-cards -o cards/b.egg b.png
egg-palettize -d result -dm result -dr result -opt -nodb cards/*.egg

The result folder has the .eggs you want.
You can create a script for make the process automatic.