Freeform Magic for Odd-likes

My freeform casting house rules

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I enjoy how games like Into the Odd and Cairn handle magic, but in one of my long term fantasy campaigns we ended up wanting a freeform magic system. We wanted it to be light though, stuff like Mage and Ars Magicka are too crunchy for me. So I cooked something up and thought maybe you might have use for it too.

It’s a cost based casting system that you can bolt onto any Odd-like. It’s inspired by Symbaroum and its focus on corruption, and the Electrum Archive.

This was battle tested for 9 months and worked well at my table.

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Casting costs

Magic can take any form the caster wishes within the constraints of the world. Classic constraints are things like not manipulating time, that sort of thing. The GM is always free to say that something is beyond the caster’s capability. This kind of discussion is part and parcel of freeform magic.

The cost of casting is levied against a stat. You could pay through mental strain (WIL), or your own flesh (STR).

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The cost of casting begins at 1.

There are five factors to consider when determining the cost of a casting. For each of these factors there are three levels. The base level costs nothing. The first level is a +1 to the cost, and the second is a +2.

Targets: One (base) - A few (+1) - Many (+2)

Duration: Instant (base) - A minute (+1) - An hour (+2)

Power (how strong the GM determines the effect to be): Small effect/d6 damage (base) - Moderate effect/d8 damage (+1) - Strong effect/d10 damage (+2)

Distance: Close (base) - Within sight (+1) - Anywhere (requires a token of the target e.g. a lock of hair) (+2)

Subtlety: Obvious (base) - Seen by those who are paying attention (+1) - Only detectable by other magic users (+2)

You’ll note that spells don’t last longer than an hour here. I handled ‘bigger’ spells through a ritual system, which I might post at some point.

Casting checks

The caster then makes a mental stat check, like WIL. If they succeed, the spell takes effect and they pay the cost. If they fail, they pay the cost and the spell doesn’t take effect.

There are a couple of conditions where a contested roll might apply, where the caster and targets both roll WIL saves to determine the victor. Circumstances like:

• If the spell has a duration beyond ‘instant’, on subsequent turns the target can attempt to break the spell.

• If a target has the means to resist spells, like a magic user or a powerful creature, they might be able to contest the spell immediately at the GM’s discretion.

Contested roll results:

• Caster fails, target succeeds. Spell effect ends.

• Caster succeeds, target fails. Spell continues.

• Caster fails, target fails. Who rolled lower wins.

• Caster succeeds, target succeeds. Who rolled lower wins.

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Traditions

Magic can be categorised into forms or traditions, e.g. ‘pyromancy’ and ‘necromancy’.

A character can only cast spells related to the traditions they have at least the rank of novice in. A rank of adept or master provides characters with reductions to costs (to a minimum cost of one).

Novice: 0 Adept: -1 Master: -2

Casters gain ranks in traditions by training in the game world, seeking teachers or finding resources like tomes or archives.

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Resources

It can be helpful to have other magic systems to inspire you when you are running freeform magic. Some of my favourites:

• Symbaroum and Into the Wyrd and Wild: Fantastic ideas for spells and rituals

• Electrum Archive: A spell generation system that can help you wrap your head around free form magic.

• Into the Odd: Arcana will help you explore how weird magic can be.