

Factorio is great, how has no one mentioned it yet? Also Dwarf Fortress, Into the breach and “FTL - Faster Than Light”.
They all have native ports and are moddable.
Factorial and FTL even have huge overhaul mods, that change most stuff so they don’t really get boring.









Why stop there? 7-6=1 9-7=2 9-6=3 11-7=4 11-6=5 7=7 6+9-7=8 9=9 6+11-7=10 11=11 7+11-6=12 6+7=13 11+9-6=14 9+6=15 9+7=16 11+6=17 11+7=18 11+9-7+6=19 11+9=20 11+9+7-6=21 6+7+9=22
and 23 I didn’t find with only + and - and each number only once.