Drug Wars is a passive game where it has a series of counters. So, you set up your production, buildings, and your army. You can attack other players, stealing their drugs and such. You can build defences as well.
The more drugs you produce, the more you get paid. I am currently getting $1 steem a day from the game whether I play it or not. Plus, you can invest excess drugs into a "heist" and you can get paid another bonus amount on top.
It earns money a lot faster than most things on the block-chain.