Brainstorming - Contested Magic

[jjordan]

In a setting where magic is commonly used at a lower level I'm looking at contested magic. Think of it as a variety of counterspell. Caster A begins a spell by summoning magic energy and shaping it to their end. Caster B reacts by attempting to disrupt or take control of (partially or completely) Caster A's magic and Caster A resists. There's a contested result.

I'm primarily interested in doing this as a sort of magical arena duel so my casters have their own alternative to pit-fighting. But I'm also interested in making it a skill that can be applied in practical situations. So I want to make sure it doesn't become too powerful. In fact, I'd rather it fell in the realm of underpowered. Not sure if I want to do this as a spell(s) or some sort of arcane feat(s).

[GaelofDarkness]

The first thing that springs to mind is if this magical energy is measured in some way - it uses a Level X spell slot or comsumes X points of mana - then the attempt to interfere with this magic could aim to reduce or even steal some part of this X, depending on how successful the attempt was. To do this the disrupter might have to bet a certain amount of their own power - a Level Y spell slot or Y points of mana - and if they botch their attempt the original caster can take some of that magic to increase their spell's power. So two pools of points: X and Y. Possible result states could look like, from best to worst: X is reduced and Y increases by the same amount, X is reduced, both X and Y are reduced, Y is reduced, Y is reduced and X increases by the same amount. How you would model those different states would depend on the kind of skills and attributes in the system you're using, as would what mechanics could fit into that naturally.

A quick sketch of how this could play out in something like DnD:
Mage A casts a spell using a level X spell slot. Mage B disrupts, drawing on a level Y spell slot. Their players roll dice - d20+spellcasting for Mage A and maybe d20+spellcasting ability without proficiency+Y for Mage B.
- Mage A beats Mage B with a critical success: Mage A gets to cast their spell as though it was cast with a level X+Y spell slot.
- Mage A beats Mage B: Mage A casts their spell as normal and Mage B loses their spell slot.
- Mage A and Mage B tie: Mage A's spell slot is reduced to X-Y, Mage B loses their spell slot.
- Mage B beats Mage A: Mage A's spell slot is reduced to X-Y, Mage B keeps their spell slot.
- Mage B beats Mage A with a critical success: Mage A's spell slot is reduced to X-Y, Mage B's spell slot turns from Y to 2Y.

This is just spitballing and I don't think this is super workable as is, it's just what fits the fiction of mages wresting power from each other in my head. EDIT: I didn't mean that the spell slot should just disappear, but that it could be reduced depending on how much power the other caster is committing, sorry.

[jjordan]

The first thing that springs to mind is if this magical energy is measured in some way - it uses a Level X spell slot or comsumes X points of mana - then the attempt to interfere with this magic could aim to reduce or even steal some part of this X, depending on how successful the attempt was. To do this the disrupter might have to bet a certain amount of their own power - a Level Y spell slot or Y points of mana - and if they botch their attempt the original caster can take some of that magic to increase their spell's power. So two pools of points: X and Y. Possible result states could look like, from best to worst: X is reduced and Y increases by the same amount, X is reduced, both X and Y are reduced, Y is reduced, Y is reduced and X increases by the same amount. How you would model those different states would depend on the kind of skills and attributes in the system you're using, as would what mechanics could fit into that naturally.

A quick sketch of how this could play out in something like DnD:
Mage A casts a spell using a level X spell slot. Mage B disrupts, drawing on a level Y spell slot. Their players roll dice - d20+spellcasting for Mage A and maybe d20+spellcasting ability without proficiency+Y for Mage B.
- Mage A beats Mage B with a critical success: Mage A gets to cast their spell as though it was cast with a level X+Y spell slot.
- Mage A beats Mage B: Mage A casts their spell as normal and Mage B loses their spell slot.
- Mage A and Mage B tie: Mage A's spell slot is reduced to X-Y, Mage B loses their spell slot.
- Mage B beats Mage A: Mage A's spell slot is reduced to X-Y, Mage B keeps their spell slot.
- Mage B beats Mage A with a critical success: Mage A's spell slot is reduced to X-Y, Mage B's spell slot turns from Y to 2Y.

This is just spitballing and I don't think this is super workable as is, it's just what fits the fiction of mages wresting power from each other in my head. EDIT: I didn't mean that the spell slot should just disappear, but that it could be reduced depending on how much power the other caster is committing, sorry.

That's the general gist of it. And I should have specified that I'm looking at D&D 5E for this.

Some more random thoughts I'm putting on 'paper':
-I want this to be fairly low level stuff. So doing it against higher level spells should be harder and carry a greater risk of harm. Increasing the level of the spell should be a fairly standard tactic to counter this.
-Thinking about making this a new type of Sorcerer meta-magic rather than a version of a counter-spell.
-I like the blowback risk for the counter-speller.

[GaelofDarkness]

Ah cool. Making it a kind of meta-magic makes sense if it's cool being restricted to sorcerers. Maybe one of the dangers is if the disruptor rolls badly, the caster can use one of their metamagic options using the sorcery points they would have used for disrupting the spell.

[Nifft]

In a setting where magic is commonly used at a lower level I'm looking at contested magic. Think of it as a variety of counterspell. Caster A begins a spell by summoning magic energy and shaping it to their end. Caster B reacts by attempting to disrupt or take control of (partially or completely) Caster A's magic and Caster A resists. There's a contested result.

I'm primarily interested in doing this as a sort of magical arena duel so my casters have their own alternative to pit-fighting. But I'm also interested in making it a skill that can be applied in practical situations. So I want to make sure it doesn't become too powerful. In fact, I'd rather it fell in the realm of underpowered. Not sure if I want to do this as a spell(s) or some sort of arcane feat(s).

This would function well in a longer-casting system, like older version of D&D (1e / oD&D), where other casters would have several segments to put forward their own "magical bids".

You might want to do a rock-paper-scissors type thing with different descriptors, like a [Fire] spell will counter a [Wood] spell, but will be countered by a [Water] spell... but at that point you'd want to come up with a balanced set of descriptors which cover the spell system. Wu Jen might be a place to start for that, though you wouldn't want to use the class itself since it's locked into a single element.

[jjordan]

This would function well in a longer-casting system, like older version of D&D (1e / oD&D), where other casters would have several segments to put forward their own "magical bids".

You might want to do a rock-paper-scissors type thing with different descriptors, like a [Fire] spell will counter a [Wood] spell, but will be countered by a [Water] spell... but at that point you'd want to come up with a balanced set of descriptors which cover the spell system. Wu Jen might be a place to start for that, though you wouldn't want to use the class itself since it's locked into a single element.

Oof. I've barely got good notions on how to do this with two casters involved. Adding three or more casters? Yikes. It's a good point, though. A system that works for 3+ will scale down to work with 2 but a system that works for 2 might not scale up to work with 3+. I should keep that in mind. I'm thinking the 5e conversion to Spell Points optional rule may be my friend in this regard.

[Nifft]

In terms of breaking up spells and "what beats what", look to other games.

Pokemon might have a reasonably well-developed elemental rock-paper-scissors system, for example.