OSR: Free-Form Magic

Part 2 is here.

source taken down

This is a magic system based on the idea that you can cast any spell you want. Or rather, produce any magical effect you wish, as there are no spells, nor any spell lists in this system. You do this by declaring what you wish to do to the Referee, who then selects a DC. Then roll 1d20+COG modifier (or your spellcasting modifier of choice). If you equal or exceed the DC, you successfully do what you tried to do.

Guidelines for DCs:

Easy: Anything a Mage could do with little to minimal effort. Unlikely to take more than a few seconds. Base DC: 5.

Moderate: Anything an experienced Mage could do somewhat easily, while a novice might struggle. Can take longer, and the longer it takes, the easier it is. Base DC: 10.

Expert: Anything a Master Mage could do easily, while all others would struggle. Base DC: 15.

Magic Attacks:

According to the rules described here, characters do not make attacks against a static AC, but against the opponent's roll. An Atk roll is calculated as 1d20+damage dice+Atk modifier. A Defense roll works the same way, but is done in reaction to an attack being done against you.

For Magical Attacks, I would set the DC for a 'hit' as the opponent's Defense roll. This will be for attacks meant to target one creature.

If an attack does something that cannot be physically blocked or parried, or targets a whole group, the Referee would instead have the targets make a Saving Throw and possibly give them a bonus or disadvantage to their saves, depending on how easy or hard what the caster is trying to do is.

To calculate damage, I would have have a spell do a base amount of damage, and then let that amount be augmented through the use of dice. For example, +1d6 per MD spent.

Example:

A fireball cast with 2 MD (1d20(1d6)+2d6) does 3d6 damage. The enemies get a save.

A jet of high-pressure water targeting one creature cast with 1 MD (1d20(1d6)+1d6) does 2d6 damage, while the enemy makes a Defense roll.

by DominikBroniek

Modifiers:

Lower the Difficulty If:

- The Mage is well-rested, unhurt, in prime condition

- The Mage is under no stress or pressure

- The Mage can take their time

- The Stars are right

- The casting is part of a ritual

- There are other Mages helping with the casting

Increase the Difficulty If:

- The Mage is seriously injured, drunk, drugged or mentally impaired

- The Mage is operating under a time limit/running out of time

- The Stars are Wrong

- There was no time for ritual preparations or safety protocol

- There are other Mages helping with the casting, and they're screwing it up in some way

Other Modifiers:

Players can lower the difficulty of their castings by including certain conditions. For example, if the player wants to include the ability to save to take half damage, this would lower the damage of a spell.

Conversely, if the player wants a spell to not have any way to defend against or have some other dangerous effects on top of the "normal" effect, that can make things harder for them.

So if the player wants to throw a fireball, but has been rolling poorly, he can tell the Referee "And if they succeed on a Save, they take half damage". The Referee should then accomodate them and lower the DC.

Or if the player has been rolling really well and wants to take a chance, he can tell the Referee, "This is an instant death spell, so if he fails a save, the enemy just dies, no matter how much HP he has left." The Referee should feel free to raise the DC a bit if the player makes such a request.

from here, artist unknown

Countering and Unbinding Spells:

Countering Elemental/Physical Spells: A Wizard can counter a damaging spell or a spell that affects them in a physical roll by striking back, as a reaction, with the opposite element or an opposing force to neutralize the effect of the spell cast.

For example, Cinnamon Jane fires a blast of fire at Gloaming Myrtle, who counters with a jet of conjured water. They both roll 1d20+(COG Modifier)+(Relevant Affinity) and if their spellcasting rolls were successful, they compare the damage they would have dealt. If Jane's roll was higher, Myrtle takes the difference in damage. For example, if Jane did 6 damage and Myrtle's water jet only did 4, then Myrtle takes 2 damage. If Myrtle's water jet did 5 damage and Jane's only did 2 however, then Myrtle would take no damage.

Unbinding Spells: When an enemy Wizard targets you with a spell, as a reaction, you can attempt to unbind the spell. When you do this, you must roll a number equal or greater than your opponent's spellcasting roll. If you succeed, you unbind the spell, causing it to produce no effect. If you fail, the spell takes effect as normal.

For example, Jasha Glitterflame attempts to turn Markus Sternshield into a toad. Jasha rolls 1d20[3]+(COG Modifier)[1]+(Relevant Affinity)[+3] for a total of 7. Markus rolls to unbind the spell and rolls 1d20[1]+(COG Modifier)[1]+(Relevant Affinity)[+2] for a total of 4. Markus becomes a toad!

Spell Misfires/Chaos and Corruption:

In the GLOG system, Chaos and Corruption not only add to the flavor of the world, but also help to balance the Wizard against the other classes, by preventing them from out-shining the other classes. This is because while a Wizard could potentially annihilate any foe or problem he is faced with magic, he could just as easily blow himself up or get turned into a toad.

In this system, a higher chance of Chaos is less necessary, as when a Wizard fails to meet the casting DC, their spell still fails.

I have created a system of Chaos and Corruption because I still feel that spell-failures are fun and interesting, but I was careful to balance this against the need to encourage creativity, so it's much less restrictive than GLOG Chaos and Corruption.

I also did not give players Doom Points or Doom in this game and it has been working out quite well, as the idea was to test the system. You could still include that element though, if you're still attached to it.

by Zhu Liu

Optional Rule: Domains:

If you're scared of letting players totally off the leash, you can add the following rules. When a player makes a Wizard, they gain control over one aspect of reality and can control that innately.

Players can only control that one aspect and it's various sub-effects. This will incentivize more clever thinking, possibly.

Example Aspects:

- The Elements: Fire, Water, Earth, Air, Lightning, etc.

- Radiation

- Sound

- Time

- Space

- Force

- Emotions/Charm

- Mind/Thoughts

- Life

- Death

- Luck/Chance

Players could also choose a lesser Aspect, in return for some sort of additional bonus at character creation. Lesser Aspects are sub-domains within one Aspect.

Example Lesser Aspects:

- Metal

- Dough/Baked Goods

- String/Yarn

- Bone

- Smoke

- Marine Animals

- Music

by Bogdan-MRK

Everything above this point is from the original post. Below I have included some notes that I scrawled down after using this system for 26 sessions.

Notes from Actually using this System:

1. It is Referee-Heavy

This will require the Referee to be quick on their feet and to adjudicate more often and in more varied situations. It can place a burden on the Referee, so be advised. If you're already running a complex world or juggling other factors, it might be a complication you might not want.

You will also have to often make rulings when some sort of interesting situation comes up. For example, how does conjuration work? Do you take the thing you are conjuring from another world or this world or are you making it out of energy? If I conjure money, is it technically stealing?

2. It frees the Wizard

Wizards can now do all the things you traditionally see in fantasy novels. It is the closest system you can make that will allow a player to role-play as a Wizard with the minimum of fuss. It lets you feel like a Wizard because you can do magic rituals, make potions, throw fireballs and everything else your favorite fictional Wizard does.

3. It Frees the Referee

Instead of having to create elaborate systems and networks of rules, the framework here can be easily applied to all sorts of other magical arts, from Alchemy, Ritual Magic, Artifice, etc. It allows you to do all sorts of magic without having to make a whole mess of rules. Also, you'll never have to make another spell list for an enemy again!

Additionally, you can freely indulge in all sorts of magical nonsense to your heart's content, without worrying about the players complaining or wondering why they can't do something because news-flash, they actually can! Instead of a player saying, "What spell did they use to do that?" Just say, "A Wizard did it and you can too, if you roll well enough!"

4. It encourages creativity

This should be obvious, but in a system where anything is possible, almost anything is possible. It will take the players a while to figure this out, but when they do, you will be surprised and impressed by what they come up with.

by SigneRJArts