A significant part of Heroes of Malkion is taken up with the various cults of the West. Each of the 'big three' Malkioni cultures - Seshnela, Loskalm, and Jonatela - has five specific cults described, and many smaller ones have two or three cults. In addition, there is quite an array of cults that are widespread throughout the Western cultures. You can find the full list at the Issaries website, if you're interested.
You'll note that many are new to print (although, in fact, several of the saints originally came from the fertile mind of Sandy Petersen). So, how did I go about designing all these new cults, and making sure that they fit in the Gloranthan mythos? The first step was to find a niche that needed filling, especially if it was one useful in-game. Some niches may be useful as background material, but can be left out of a book with limited word count - for instance, Saint Jandaris, patron saint of glassworkers, gets a mention in LotW3, but he doesn't have a full write-up. (Perhaps he will, some day, if somebody really needs such a thing, but he wasn't a high priority for me). We need saints and schools to cover entertainers, merchants, scholars, and a number of other special professions, such as heralds. There has to be a good variety of warrior saints, because warriors are a popular character type, and similarly for wizardry/sorcery schools, where there are all sorts of concepts one can play about with.
And, personally, I like healers, so there are quite a number of healer cults in the book, too. Not as many as warriors, maybe, but putting people back together can be as varied an art as taking them apart in the first place, so there's a good range; Saint Falerine is fairly light and fluffy, while, at the opposite extreme, Saint Anazieta is positively scary.
The classic example of me mucking about with character roles is, as many of you probably already know, a certain pair of warrior saints. Chaos isn't quite as big a bogey-man for the Malkioni as it is for, say, the Praxians, but it's certainly well up there as a major foe, being opposed to Law and all. So we need a cult of specialist Chaos-fighters. But the last thing we want is a clone of Storm Bull, so... well, what is Chaos, really, from the Malkioni perspective? Chaos is about the breakdown of society, failure to respect the law, of allowing your baser nature to control your rational mind, replacing Logic with the obsessions of the Id. It therefore follows (said Saint Zemuron) that any move in that direction is a move towards Chaos. The result? A cult of wine-sipping, quiche-eating, frightfully polite chaps who do their best to maintain decorum. And happen to be deadly with a sword and lance, and will hack the tentacles off a charnjibber as soon as look at it.
Of course, as soon as I'd written them up, that rather left the niche filled by Storm Bull/Urox among the barbarians empty. Sometimes you just want to go nuts as a player, and not have to worry about maintaining your composure and writing clever poetry about it afterwards. If you're the sort of player who thinks that all this chivalry stuff is a bit nancy, and just wants to lay about you with an axe... for you, we have the cult of Saint Hasterax. And most of Jonatela, to be fair, but Hasterax is more widespread. Hasteraxi are single-minded nutters, and sometimes that's just what you want in a game.
OK, so now you know that you need a saint for Love, Romance, & Fluffy Bunnies, or whatever it may be. Now what do you do? I'll return to that later...