As we know many spells have two different versions, one of which is improved in some way at the cost of greater drain. Should you allow players to take the improved version of a spell without taking the regular version first? I didn't see any rules against it (and please point me in the right direction if I'm overlooking something), but it doesn't make sense to me that a character would know how to cast Detect Life (extended) in ForcexMagx10 meter, but yet couldn't do it in ForcexMag meters if he wished. Or a character that could cast Improved Invis, but not Invis, or Mass Sight Removal but not Sight Removal etc.

No, there's no prerequisites in spells. You can have Improved Invisibility without Invisibility, or Manaball without Manabolt.

The reasoning behind it is that spells are devised with certain specifications: an area spell is a different symbolic formula than a spell that targets a single target, and probably has a higher drain as well.

...y'know though, it doesn't sound like such a bad houserule idea...

*nods* There are hundreds, probably thousands or more actually, different formula for the casting of a simple fireball. So, while I would probably let a character crafting a spell formula get a couple bonus dice if he had a similar forumla to reference (crafting Detect Life when he already knows the extended version for instance) but they are two completely different things in the system. One might take the mana and saturate the area with it as though a mist and anything that disturbs the mist pings on the radar in a ripple like effect(Detect Life) and the other might create, with the same amount of mana, a latticelike effect of very very thin mana strands that interlace over a much larger area and work like a spider's web(Detect Magic, Extended). Other than the fact that they use mana to sense things they are very different, and you can see which one would be more complex to hold in your head and more strenuous.(Detect Life, Extended) represented by the greater drain for the same amount of mana.

Chris

EDIT: I agree, Fortune.

I kind of like that you can take the more powerful versions of spells without the weaker ones. The thing about it is, you don't have the option of using the weaker one when you do that, meaning you're always stuck with the higher drain. That works for me. You want more choices, you pay for them. If you don't want those choices, more power to you.

That said, though I wouldn't implement it in my game, I wouldn't be opposed to giving a character a 1 karma discount on learning an existing spell (not one that they wrote) that is a direct variation of one he already knows. Like a character with Lightning Bolt learning Lightning Ball, or learning the extended version of a detection spell you already know.

I run a house rule in my games ranking each spell in difficulty. The mage must then have a sorcery skill equal to that rank in order to cast the spell. I was irritated at seeing mages start with magic at 6 and sorcery at 2. It also gives the players more of a sense of improvement when they raise the skill.