Long time ago, I played avernum demo. Then avernum 2 and 3 demos.
Much much later, I got avernum, 2, 3, blades. I didn't like 4-6.
It tried Avernum demo again but the way it worked was a bit different from 2-blades, enough to annoy me so much I couldn't even come close to finishing demo.
Maybe now I can finally play it when this comes.