- Is this rule balanced compared to e.g. the Mage?
Pretty much. Remember, the spells selected are supposed to conform to the "spheres/aspects" of the deity worshiped by the Cleric. A cleric God of the Moon will NOT, EVER have fire bolts or lightning bolts as part of their spell repertoire.
This has potential for abuse, and it is up to the GM to make sure that no abuse occurs. The GM always has the final say as to what spells are acceptable or not.
In several of the issues of HARPer's Bazaar, I give samples of Clerics where I (acting as GM) have set up the spells for the Cleric as well as the skill categories. I recommend that a GM do this for any setting he is working with. I have attached an image of one example from HB #3.
In this sample, the his base is 14 spells, and then he gets to choose 6 from a short list. All the spells in the sample work for the Clerical order described, so there is no chance of him getting a "wrong spell", and there is still plenty of room for individuality in different clerics of the order.. But I also gave the profession a special ability to make up for the large amount of the flexibility that had been removed.
The Cleric in the core book is generic because there is no way to tell what sort of gods are present in the setting.
Can a cleric also choose spells from the mage sphere?
Yes, but only IF those spells are right for the deity -- this is a GM decision.
- What exactly is meant with the term "Categories"?
Skill Categories -- read the upper left hand section of page 11 -- each profession gets a number of skill categories as Favored, and skills in those categories cost 2 points per rank, everything else costing 4 points per rank.
To see a list of skills, sorted by category, look at the table on page 11.
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