QUOTE (Yerameyahu @ Oct 19 2010, 12:05 PM)
There are some other positive and negative Astral modifiers, but yeah, you did make it sound like steamrolling: a high-powered Mage with a high-powered Spirit active, slinging high-powered spells… against Joe Security with *no* mods?
However, Threshold 0 is Obvious, isn't it? Even if you houserule it up to 8, that's still 0.
It's not clear to me which Threshold you use, the Noticing Magic one or the Perception Test Thresholds table? I would think you'd use the Noticing Magic formula in place of the other, especially since the fluff in the Noticing Magic says:
QUOTE
Just how obvious are magical skills? Not very, since most spells and spirits have little, if any, visible effect in the physical world (unless the magician prefers to have flashy effects, or her tradition calls for it).
So, again using my 8-Force houserule and a Force 6 spell you'd have Threshold 2 for any Perception Test to notice the casting, even if the observer is on the Astral. I could be wrong, of course.
The most recent example of my team using Concealment to their advantage against powerful adversaries can be summed up in: (spoiler for DotA: Midnight)
[ Spoiler ]
The final encounter in Midnight is against a powerful Blood Mage and some pretty serious street sam and physad support. The Deep Lacuna cave where it takes place has plenty of cover in the form of stalagmites and cargo crates. The team knew they were facing serious opposition, so the magician summoned up his Force 8 spirit, using Edge to help resist Drain, and they made their way to the cave while Concealed. The pool where the team surfaced was on the opposite side of the cavern from the antagonists and there were no clear lines of sight across the cave. Poor ambush setup, if you ask me, but I didn't think to change that. So, without going into excruciating detail, the team was able to get into cover positions using Infiltration and Force 8 Concealment. They ambush the ambushers and the team's mage manages to stay hidden for the crucial Initiative Pass while the identity of the Blood Mage is made obvious by his use of an Anchored Smoke spell. I guess the author was trying to play up the overconfidence of the Blood Mage, but making yourself stand out like that seems like a very bad idea. Anyway, concentrated weapons fire took out the Blood Mage quickly and once Counterspelling was down unopposed magicl helped even the odds and after a still very tough fight the team came out on top.
Edit: Of course, I may simply have just made the case that the encounter design in Midnight blows.