There's a huge number of games that use the d20 System, including d20 Modern. I've been looking for mods that adapt d20 Modern, or just the d20 System in general. I feel there must be a list somewhere ...
There are 2 versions of Prime Directive d20, one based on the D&D 3.5 PHB and the other based on D20 Modern. Are there any noteworthy differences between the two versions, or did they just make a ...