There are a couple of effects I can see:
1) extra damage to an attack - this could be a simple Invoke of an Aspect: Flaming Body; Sandstorms Are Mine To Command; Uncanny Strike
2) maneuvers in the same round as an attack - this would have to be some sort of supplemental or free action, unless the creature has a power/feat that allows it to split shifts between an attack and a maneuver
3) simple damage shield, such that anyone who touches me gets hurt - this one is new, and I don't see anything like it in DFRPG, yet it is in the idiom for many fantastic/magical creatures, like fire elementals, demons, and more.
4) environmental damage effect - this has been mentioned before. I liked the Living Lightning effect.
The immediate example I wanted to stat was the
aigamuxa conversion I just posted.
It has a power "In desert or sandy terrain, an aigamuxa can generate a powerful magical sandstorm around itself, which it can use to blind, cause damage, extinguish lights, or perform other maneuvers." This is supposed to be an effect it can generate while it is performing other actions.
I posted two options for making the power, neither of which could necessarily be used on a continuous basis while Fists attacks are going on, though creating a Scene Aspect could be done with either method:
A. Channelling (Sandstorms) [-2]
or
B. Custom Power: Summon Sandstorm [-3]:
- Breath Weapon (Sandstorms) [-2]
- Wide Breath [-2] Your breath weapon affects everyone in a single zone.
- Limited: requires ambient sand or other particulate matter [+1]
Do you mean something like Aura of Fear that higher level undead get in D&D. If you were porting something like that to DFRP I would say anyone who dose not beat the monsters intimidate skill within the Area (not a roll just the skill) get the temparary aspect scared, this would probably be a -2 power potent but not game breaking as it would only give one free tag per enemy.
That would be a good one. Ferrovax would probably have something similar in his true form.