Hey /tg/, I had a really odd idea for a game.

The setting is a single planet, relatively ordinary, save for the atmosphere. The breathable gas on the planet comes in two distinct varieties, one of which blocks certain wavelengths of light, the other blocking other wavelengths.

This causes a situation where species adapted to gas A cannot see well in gas B, and vice versa, creating large, shifting areas where it is dangerous and difficult to travel.

The sentient race on this world lives in both, but the two civilisations are almost completely separate, simply because they would never willingly go into the other gas. However, children of the race can see through both, and often go wandering between the two gasses if they're left unattended.

Of course, when a child is missing all the warriors etc go out looking for them, heavily armed in case of attack by the things form the fog- the other civilsation, who, upon seeing a child being "chased" by a mob of heavily armed beings goes to "save" it.

The children of the races are identical, only changing at puberty, permanantly adapting to one of the environments/cultures and assuming a more adult form. This, combined with the fearsome and scary nature of the masks and armour worn by warriors, means each sentient civilisation essentially considers the other civilisation a race of demons in the mist.

I'm still thinking through ideas for how a game would work, and what the PC's would be- maybe normal tribesmen, perhaps "Shadowwalkers" who retained the ability to see in both gasses after childhood. Might be interesting.

Any thoughts?