Crossposting this from the now-defunct shadowrun.com forums.
So I've been thinking about this, and Alchemy as it is in the core book is one of the hardest aspects of the game to master, at least as far as magic is concerned. It has the potential to be really powerful (even if you don't listen to the people who want to do bullets with contact fireball preparations on them, or similar drek), but it can also go off horribly wrong, more so than even regular spellcasting. To me, the proper way to think of it is in separating which spells work better as preparations, and which work better as spells.
Now, like many people, I started gaming with D&D, and this colors a lot of the way I think about RPGs. As I think about it, comparing Spellcasting to Alchemy is a lot like comparing Sorcerers to Wizards in D&D. Both are spellcasters, yes, but a Sorcerer is a more 'seat of your pants' style, and is relatively easy for players new to magic-users to play. Wizards, on the other hand, live or die by the choices they make in advance, and have extremely limited resources in spells, making them a much harder class to master and play well, since they have less adaptability than the Sorcerer does. To translate this back into Shadowrun, this means that a mage using Spellcasting (or an Aspected Sorcerer) is able to adapt to situations on the fly, making them much easier to play. However, for those who put the time into mastering the class, or those who have certain playstyles, the mage using Alchemy (or an Aspected Artificer) can be incredibly powerful, and just as rewarding. But I would not recommend it for players who aren't willing to put the work in to master the mechanics.
So what are the best ways to use alchemy, then? The way I see it, there are a few places where alchemy shines, and a few places where it is... not so good.
Where it Shines:
--When you have long prep time beforehand. The biggest advantage of preparations is that you take the drain ahead of time, and can sleep off the effects (or use a medkit on yourself if it is physical) and be in prime shape when it comes time to do the run. Not having to manage drain for high end spells during the middle of a run is a big thing.
--Reagents. Low to mid force preparations using reagents to boost the limit (and potentially the Potency) is the name of the game here. This works best for spells that only require 3-4 hits to be really effective, since the Force of the spell will still act as the limit on the test when the preparation goes off, but high potency adds to that test, and makes the preparation last longer, allowing you to sleep off the drain before the run. Likewise, keeping the force low will reduce the opposed roll when creating the preparation. For sustained effects (like a Mindlink spell) that only require a single hit to work, the fact that the preparation will sustain the spell for (Potency) minutes can make this a very useful thing indeed.
--Battlefield Control spells. Any type of wall, Area debuff effects (Chaotic World, Mass Agony), or static interference spells (like the Shadow spell), or similar effects. These things can change the flow of battle, turning what would otherwise be a hellacious fight into something more manageable. These work best as Command preparations, where you use a force of 2-4 with reagents to boost the limit on the alchemy test. This lets you prepare something that has a decently high Potency, while keeping the drain minimal, and with less chance of wasting the effect (which is more of a risk at high Force).
--(Most) Health Spells. With some health spells, such as Increase (Attribute) or Increase Reflexes, it is better to just use a spell and a sustaining focus, but with most other health spells, especially the ones that need to be sustained to become permanent like Heal and Stabilize, a preparation is more effective, as it allows you to do other things while the preparation sustains the effect for you, meaning you don't have the -2 penalty for each effect. This allows you to do multiple healings in short order. If I have to tell you why being able to heal up your team on the run between two gunfights without taking stacking -2 penalties is a good thing, you're playing the wrong game.
--Traps and ambushes. This is primarily dealing with combat spells, but also applies to emergency measures you take to prepare against traps and ambushes. While in most cases combat spells are not that effective as preparations (I'll get to my reasons for that later), there are cases when they are quite useful. How useful will depend on your play style. I find that these things work best with a black trenchcoat style game, as a pink mohawk game is typically not going to have the stealth run ahead of time to set up the traps, and so on. Also, the form your preparations take will make a difference here. Someone might not notice paper onmyoujo talismans taped to a wall, or the painted rock at the side of the road, but something like a potion or a wood carving might be more noticable. This also is very useful for distractions when you don't want to be around when the big booms happen, ESPECIALLY when you set the things up to cause sympathetic explosions (like when you slip a Fireball talisman into an ammo dump you need to go away as a distraction). On the 'preparing for an ambush' side of things, this mostly relates to a very small set of spells that allow someone to get out of a sticky situation if their cover is blown. Mainly: Invisibility, Stealth, Combat Sense, Armor, and some battlefield control spells. If the spellcaster is not the one who will be using the preparation, then these work best as Contact trigger preparations, provided you have some way to keep the person's aura from touching it before you need it. Sending the face into a high risk negotiation with a couple flasks with potions of Armor and Invisibility may keep him alive long enough to get out of dodge if things go south.
Where it Falls Behind:
--Random Encounters. All right, this is another D&D-ism of mine cropping up, but you know what I mean. Sometimes you know you're going into a fight. You're not going to just knock on the door of the Yakuza warehouse to ask them nicely for the thing they stole from the Triads without exchanging a couple 'arguments' in the process. Sometimes, the fight comes to you when you're least expecting it. The downside of preparation types is that when they are in situations they didn't prepare for, like a troll showing up at their doorstep with a Panther XXL, then they're struggling to get things together.The only combat spells that are any good as preparations are area effects, since you don't need to make the attack roll.
--Combat Spells. Outside of a few situations (mainly traps and ambushes), combat spells do not work well as preparations. Using combat spells in actual combat requires a degree of flexibility that preparations just don't have. Since the Force of the preparation is fixed, you can't, say, kick it up a notch when you really, absolutely need to drop that troll with the grenade launcher before he turns your group into chunky salsa.
--Opposed tests. Also playing into the reasons why combat spells (and most detection spells) are worthless as preparations, you have an opposed roll to create the preparation, and then have to make an additional opposed roll to activate it, but your dice pool is dependent on the net hits you got on the first roll. This problem gets worse the higher the Force you cast at, making high level effects nearly impossible to pull off. While a Force 12 Fireball might only need one solid hit on the spellcasting test to make Bad Things(tm) happen, you run a high risk of wasting the preparation altogether when you have to average 5 hits just to get a Potency of 1.
--Sustained spells. For some spells, like Physical Barrier, having the spell sustain itself is just fine. For others, you need either greater time than the preparation allows, or more flexibility than is provided with preparations. Increase Reflexes is something you generally would like to have up when you go into the building, and keep up until you are clear, possibly using a sustaining focus to do so. Control Actions is too finicky to leave to a preparation. Likewise, you don't want the Levitate spell to cut out while you're still twenty feet from that balcony you needed to get to on the 63rd floor.
I welcome your thoughts.
