Is there any rules for wielding two weapons, one in each hand, and attacking with both? Do we assume for simplicity that there's no special rules for it and if you're attacking with two weapons you simply are?
I'd like to create a move about it but I don't know if I missed anything first.
If you want to wield two weapons, just describe that you're wielding two weapons when you hack and slash. No additional moves required. The Ranger move is just a way to get a mechanical bonus—in this case, more damage.
Note that fighting with two weapons will hinder other actions you're taking, like whenever you're in combat or have your weapons drawn. Your descriptions now have to include that your hands are full.
You could also make a custom move, if your class doesn't have an advanced move that lets you pick a move from the Ranger class or if you want a different benefit.
Anyone can use two weapons at once. The primary advantage is that you can pair weapons with different ranges: a sword for when they're a few steps away and a dagger in case they get in close, for example.
The ranger's move is a special case: taking that move reflects training in striking with both at once and gives you bonus damage for it.
The Ranger has an advanced move that does precisely that.
VIPER STRIKE When strike an enemy with two weapons at once, add an extra 1d4 damage for your off-hand strike.
