Could it be possible to make games for KaiOS with C3?
Basically, HTML5 apps/games should work with the OS, but it's intended for lower-end devices... There have been some performance issues with C2/C3 games in the mobile field, but maybe with the new runtime?
KaiOS is based on Mozilla's open source B2G OS. The apps are built purely with HTML/JS/CSS stack and any web application/website that is mobile friendly can be an app with just minor modifications. inbuilt webIDE can be used to build apps for Mozilla OS, see more here.
There will be quite a big market in developing countries, and for instance, Nokia is coming up with a new KaiOS phone 8110 4G.