Who controls a single subject targeted by two Rego spells?

Games Discussion Ars Magica
1

Assuming two mages (or supernatural creatures using powers) are attempting to control the same subject using similar rego magic - who wins?

Example: Mage A uses a ReHe (5 control entire plant + 2 voice + 1 concentration + 0 individual) 20 to target a thorn bush and successfully casts the spell. Mage B then casts an identical spell on the same plant and successfully casts the spell. Who now controls the plant?

Some possibilities:

  1. The higher casting total
  2. The more recently cast spell
  3. The higher magnitude spell (doesn't apply in this case, but might in others)
  4. Both mages must roll concentration each round to "fight" for control (highest success wins)
  5. The mage who has the highest Form Bonus in Herbam (i.e. He / 5 rounded up)

Your alternative suggestions gratefully appreciated.

2

We generally do it by spell base, then by penetration.

If both are equal I would probably go with Finesse as they wrestle for control of it.

3

Noble's Parma on RAW, but I'd probably have the characters make contested Finesse rolls.

4

I'd lean toward contested finesse rolls, too. Spells, don't have a penetration value to be overcome, so it's the ability to exercise control over your own magic, when competing magic might be interfering, so finesse is apropos, IMO.

5

Do Faerie or Magical creatures have Finesse as a skill? If a Faerie and Mage are both attempting to control the plant, are they skill contesting Finesse rolls or something else?

6

I would also use opposed Finesse rolls. In the situation mentioned above; creatures can have Finesse, but it is rare. I would rule that since the creature has the power, it should be good at controlling the plant (or whatever), and it uses Might/5 in lieu of Finesse. if the creature should have superior control over the plant (i.e. is the spirit of that plant), then I might use Might/3 (or more).

Mark

7

I'd go with "Who had the higher casting total", but that's just me. After all, if you're putting more raw power into the effect, it should be more potent.

RAW hints at this with the fact a higher level Aegis always overrides a lower level Aegis, etc.