Update: The final draft of the ACKS Heroic Fantasy Handbook contains rules for “generic” reagents that I’ll use instead of the post below.
I really like the idea in ACKS of using monster parts as special components for creating magical items. The Lairs & Encounters (L&E) book even includes extensive tables for which monster bits correspond to each particular spells.
This is really neat in theory, but super fiddly in practice. The Pyromancer wants to create a magic item with burning hands? Better hope you can get some laga slag from an animated stone statue, or some hell hound teeth, or flame salamander ichor.
In my current Black City campaign, the PCs are using generalized magic reagents as special components for their magical trinkets. This loses a lot of flavour, but I like not having to track each special component individually.
I figure I can have it both ways – cool-sounding monster bits plus easy-to-use generic reagents… Alchemists will preserve their special components (in metamphora, introduced in L&E), but also distill them into generic magic reagents.
A fully proficient alchemist (e.g., three ranks in the Alchemy proficiency) can distill special components into generic magic reagents. These magic reagents can be used for the purpose of any magic research (kind of like Azoth from ACKS Dwimmermount).
In the Black City, magic reagents are only available from the Tolberts at a cost of four times their usable value (i.e., 10gp worth of magic reagents will cost you 40gp). The Elder Tolbert is a fully-proficient alchemist, if the PCs ever need his service.