My first idea is that if you get power from a deity (officially confirmed by Ao) you are a cleric (or paladin if you are more on the warrior side).
If you get powers from another powerful being you are a warlock.
Now its more like:
Characters can get magic powers from powerful beings or other forces.
The rest is just game mechanics.
How you get power from that entity and what relationship you have with it is up to your own imagination.
Right now I have problems to understand the difference between a cleric of a demon lord and a fiend warlock.
Prof. Dr. Dr. Mad S. Tist
World leading expert of artificial stupidity.
Because there are too many people who work on artificial intelligence already
