Entschuldige, da habe ich mich falsch ausgedrückt.
Um Dispel Magic auf einen Zauber zu wirken, muss ich ihn in Pathfinder wohl sehen können, laut der letzten Aussage unseres Spielleiters.
Muss man nicht. Im Dispel Magic Text finden sich Anhaltspunkte dafür, dass man eine magische Aura sehen müsste:
Dispel Magic
School abjuration; Level bard 3, cleric 3, druid 4, paladin 3, sorcerer/wizard 3
Casting Time 1 standard action
Components V, S
Range medium (100 ft. + 10 ft./level)
Target or Area one spellcaster, creature, or object
Duration instantaneous
Saving Throw none; Spell Resistance no
You can use dispel magic to end one ongoing spell that has been cast on a creature or object, to temporarily suppress the magical abilities of a magic item, or to counter another spellcaster's spell. A dispelled spell ends as if its duration had expired. Some spells, as detailed in their descriptions, can't be defeated by dispel magic. Dispel magic can dispel (but not counter) spell-like effects just as it does spells. The effect of a spell with an instantaneous duration can't be dispelled, because the magical effect is already over before the dispel magic can take effect.
You choose to use dispel magic in one of two ways: a targeted dispel or a counterspell.
Targeted Dispel: One object, creature, or spell is the target of the dispel magic spell. You make one dispel check (1d20 + your caster level) and compare that to the spell with highest caster level (DC = 11 + the spell's caster level). If successful, that spell ends. If not, compare the same result to the spell with the next highest caster level. Repeat this process until you have dispelled one spell affecting the target, or you have failed to dispel every spell.
For example, a 7th-level caster casts dispel magic, targeting a creature affected by stoneskin (caster level 12th) and fly (caster level 6th). The caster level check results in a 19. This check is not high enough to end the stoneskin (which would have required a 23 or higher), but it is high enough to end the fly (which only required a 17). Had the dispel check resulted in a 23 or higher, the stoneskin would have been dispelled, leaving the fly intact. Had the dispel check been a 16 or less, no spells would have been affected.
You can also use a targeted dispel to specifically end one spell affecting the target or one spell affecting an area (such as a wall of fire). You must name the specific spell effect to be targeted in this way. If your caster level check is equal to or higher than the DC of that spell, it ends. No other spells or effects on the target are dispelled if your check is not high enough to end the targeted effect.
If you target an object or creature that is the effect of an ongoing spell (such as a monster summoned by summon monster), you make a dispel check to end the spell that conjured the object or creature.
If the object that you target is a magic item, you make a dispel check against the item's caster level (DC = 11 + the item's caster level). If you succeed, all the item's magical properties are suppressed for 1d4 rounds, after which the item recovers its magical properties. A suppressed item becomes nonmagical for the duration of the effect. An interdimensional opening (such as a bag of holding) is temporarily closed. A magic item's physical properties are unchanged: A suppressed magic sword is still a sword (a masterwork sword, in fact). Artifacts and deities are unaffected by mortal magic such as this.
You automatically succeed on your dispel check against any spell that you cast yourself.
Counterspell: When dispel magic is used in this way, the spell targets a spellcaster and is cast as a counterspell. Unlike a true counterspell, however, dispel magic may not work; you must make a dispel check to counter the other spellcaster's spell.
Siehe hier:
http://www.d20pfsrd.com/magic/all-spells---final/dispel-magicDer Zauber ist im Vergleich zu D&D 3.5 eh schon genug abgeschwächt worden. Ihn noch weiter abzuschwächen, ist als SL eigentlich nicht wirklich vertretbar. Hausregeln sind ja schön und gut, aber das geht doch etwas zu weit und das ist eine Hausregel, die einen Zauber weiter beschneidet, der ja eigentlich eh schon weiter abgeschwächt worden ist.
Edit: Aber mal noch eine andere Anmerkung: Wenn der Charakter darauf spekuliert, dass der Feind eine magische Feuerresistenz hat (die prinzipiell mal bannbar ist) und das gezielt bannen will und solch eine Magie aber in Wirklichkeit nicht auf dem Ziel liegt, dann ist der Dispel Magic Zauber halt verschwendet, weil etwas gebannt werden sollte, was einfach nicht auf dem Ziel lag. Ganz einfach...
Auf der anderen Seite darf man allerdings eines nie vergessen: Man bannt vom Prinzip her magische Effekte! Nur weil man den Zaubernamen nicht weiß, kann man trotzdem die komische Granit-Haut bannen, die den Nahkämpfern Probleme bereitet den Zauberwirker effizient zu verwunden
Falls das allerdings eine Su war oder etwas "nicht-magisches" hat man halt Pech gehabt...
