Very colourful and very nicely done. They are certainly different from the usual fantasy fare and all the better for it.
Old Glory's notion when starting this project right before the pandemic was to try to create a non-Tolkien fantasy world. He isn't anti-Tolkien, but there is plenty of that, and he was looking for something a little different. This is not Dorothy and Toto or any of the recent, dark adaptations. Ozz (intentionally spelled with two Zs) is an earth-based, post-apocalyptic, black powder fantasy game. The "last great war" ended with someone deploying the madness bombs that ended the war but threw the world into chaos. After several hundred years, Zoroaster the Wizard arrives from the West and begins to reorganize. A residual effect of the madness bombs is that residents of Ozz have a color mania. The game is not dark. While there are canonical colors (based on those from the Baum books), players can really do as they please with their painting schemes. I have enjoyed using colors from my paint collection that I don't often get to use.
There are a number of factions, including Munchkins, Winkies, Gillikins, Quadlings, Nomes, and others. A bag from Old Glory or Sally 4th creates a unit. A player needs 4-6 units depending their goodness (and cost).
As the author, I am biased, but people who have tried the rules have really liked them at conventions and shows. They were designed to be bloody and dynamic with an old-school feel but modern, streamlined mechanics. The system was adopted for general fantasy (Wars of Orcs and Dwarves). WOOD is a "bring whatever figures you have" system, so they provide the opportunity to breathe new life into long disused figures. I have been enjoying combinding fantasy figures from the 1970s with newer figures to create my orc and hobbit armies. I am also in the midst of adapting the system for the Napoleonic Wars, and that is going very well.