It's really not that bad. It'd just be a system or room/char flags that affect how much latent energy is available to work with and how effective a spell is. It's not trivial but it's not that bad to code, either.
There wouldn't be much point in it for purely roleplay purposes, though.
But it can accent everything with a bit of flair! If you do a bit of fiery magic in a room that's laden with fire energies, its potency could be a lot more visible. This wouldn't be too hard to do, really. Every room (and zone) can have their own fluctuations, changed by the weather, player interaction, and so on. Doing fire magic would draw some of that pooled energy.
What I had planned to do (and should be simple enough in theory) is just adapt the introduction code that was already in the codebase I was working from to identify people by scent. That codebase already had a fairly extensive tracking system so it'd mostly just be a matter of tying it together than then deciding how you wanted it displayed on the map (assuming you were using one).
It would be fairly easy to apply a 'scent' description on rooms or objects if the builder wanted to use those for clues about an area. Making that kinda dynamic would be an interesting problem but you might be able to hack something together with mob/room progs.
I'm mostly done with my introduction code, so it shouldn't be a tremendous task to add scent to it, as well. How did you imagine it working? Seeing someone as "a being smelling of sewer", then being able to recognize them as "George" when you later discover the smelly-being's name? Perhaps something as simple as giving everyone a 'scent appearance', and depending on the viewer, use one or the other.
Smell could be influenced by where a character spends their time (sewers add to their foul odor, for instance). Objects/rooms could definitely have scents as well, and a "sniff" code could be similar to some sort of tracking, but instead pulling scents from nearby rooms/people/things.
Ideally this system would just be built from the ground up, and making it dynamic wouldn't be too tough. I've a few ideas already, just need to detail out all what the purposes would be.
