diff --git a/src/gfx_func.h b/src/gfx_func.h
--- a/src/gfx_func.h
+++ b/src/gfx_func.h
@@ -178,8 +178,6 @@ TextColour GetContrastColour(uint8 backg
  */
 extern byte _colour_gradient[COLOUR_END][8];
 
-extern bool _palette_remap_grf[];
-
 /**
  * Return the colour for a particular greyscale level.
  * @param level Intensity, 0 = black, 15 = white