How to Play Midgaard
The Midgaard Players' Guide
Moral alignment is a key concept in Midgaard. Your characters can become Evil, Good, or Neutral, and this evolution will impact the ways in which they experience the world, the Items they're able to use, and many other things.
In Midgaard, all characters are born Neutral. Your actions will cause you to drift from your initially perfect Neutral alignment; if that goes far enough, you'll become Evil or Good automatically.
In generally, killing something causes you to drift opposite to the victim's alignment. Kill a Good NPC, you'll drift Evil, and vice-versa.
This may not be what you want. You may find that to keep yourself aligned "properly" you'll have to kill some things you otherwise might not. For example, you may covet some special armor which will not allow itself to be worn by Evil characters. If you're currently Evil, it'll shock you if you try to wear it. Before you'll be able to use it, you'll have to bring your alignment to at least Neutral, and, to do that, you'll have to kill enough Evil NPCs. It's a dog-eat-dog world out there.
Keep an eye on your Alignment with the command of the same name.