Backlash after magic use
 

I'm thinking of a backlash/nuisance effect for Magery. For a period of time after casting your spell, you open yourself up, making you more susceptible to hostile magic. This means -5 or -10 (still working on it - -10 means you basically can't resist anything) to all resistance roll.

Let's say -5 to all resistance rolls for 1 minute. What do you think this should be worth?

Re: Backlash after magic use
 

I'll jump in hastily with -10 points were it a Disad, which is to say -10%. Points of comparison: reversed Magic Resistance (2/level). Cheaper than the example malus to reaction rolls (5% per -1), but the scope is more limited (pretty much enemy mages in combat, not everyone, and no one's going to mob you with torches, pitchforks, and hashtags because you cast a spell). Also reverse Resistant (were magic Very Common, +5 would be between 10 and 15 points; Common, 5-8 points, so 10 would be splitting the difference.)

Might want to phrase it as "after using your Magery", just to cover the case of the Magery 0 non-spellcaster that just wants to sense magic items, as well as other corner cases like vulnerability while enchanting S&S, and whatever else I've forgotten that's not "casting a spell").

IMO, -10 is punitive enough that I wouldn't take it for -20% to Magery. Probably even higher. -3 / -8 as "anti-Resistant" might sell better.

Re: Backlash after magic use
 

Magic Susceptibility is -3/level. Hmm... -15% perhaps.

Re: Backlash after magic use
 

The problem with that kind of limitations is that they can be *very* bad if someone know about it and exploit it, or during battle, but do absolutely nothing when there is no hostility around.

Treating it as an "aftermath" : it doesn't hinder magery, it take effect "after."
So, it is half the cost of a temporary disadvantage limitation.
5 level of Magic Susceptibility would be -15cp, so -8% for aftermath(Magic Susceptibility 5) (last 10 minutes)

Re: Backlash after magic use
 

Or maybe it's better to buy it as Magic Susceptibility (only after spellcasting, -xx). But I'm uncertain about limiting disadvantages.

Re: Backlash after magic use
 

It's like a sideways interpretation of post-combat shakes through the lens of magic.

Post-magic shakes.

Re: Backlash after magic use
 

Magic Susceptability 5 [-15] is -15% as a temporary disadvantage, so it would be worth -7% as an Aftermath limitation.

10 levels would definitely be easier math, -30% halved to -15%

I don't see a stated upper limit for this disadvantage but there probably should be one like with standard susceptability (can't reduce HT below 3)

Aftermath only works after the advantage (like magery) shuts off though.

Re: Backlash after magic use
 

And that's exactly what I'd do. Use Post-Combat Shakes as a base and then require all magic users to have it. Adding it to magery means that when you use magery it affects you, but you could just forgo the bonus from that talent and cast normally. I suppose you could invent a new modifier to magery so that this happens when you cast, but "supernatural" Post-Combat Shakes is the better option I'd think.

Re: Backlash after magic use
 

Yeah, forgot about that one. I thought it was odd that it wasn't already there ;)

Re: Backlash after magic use
 

If you're planning to make this the way magery works for everyone in your setting, or even a significant number, think about what it will mean for mage vs mage situations. If all or most magery works this way, of course your enemy knows it. Magical combatants will start very slowly, trying to get the other to "shoot first", so they can immediately follow up with an irresistible spell.