[Kristoffer O]

Not sure of the exact numbers. I guess it works like this:

Magic: (site freq) + 30
Waste: (site freq) + 20
Swamp: (site freq) + 20
Mountain: (site freq) + 10
Forest: (site freq) + 10
Farm: (site freq) - 20

Only the most beneficial counts.

If site: Check what site. Random.
If site not possible: Reroll.
If site unique and already in the game: Reroll.
If site possible and rare: Reroll once.

Many nature sites are common but restricted to forests etc.

Unique sites are also rare or common. Inkpot end is unique and common. Crown of Darkness is rare.

No blood under water IIRC. Not sure about unholy.