At its core, all magic is a manifestation of the wielder's will. The mechanical Schools of magic represent education in the various methods used to enact that will upon the world depending on the desired result.

For the purposes of casting magic, there are two Pools you will need to understand.

Power is the representation of a person's raw magical 'oomph'.

Control is the representation of a person's ability to exert conscious influence over a spell they are casting.

You do not need dots in a School to attempt magic from that School.

The first step in casting magic is to roll Power vs 6. Count the number of successes.

Next, you will roll Control vs 10. Count the number of successes.

(There is an on grid command that will do these simultaneously via +cast)

Consult the Spell List page to identify which level a spell is.

Level Successes Required
First Year 1
Second Year 2
Third Year 2
Fourth Year 2
Fifth Year 3
Sixth Year 3
Seventh Year 3
Adult 4
Unforgiveable 5

These are the number of Power successes you require to make a spell happen. If the number of successes you can count is less than that number, the spell fizzles. If it is equal to that number, the spell is successful.

However, this is where Control comes in. Each Power success is only well applied if it can be paired with a Control success. If you have enough Power successes for a successful spell, but fewer Control successes than Power successes, you have what is call an Overshoot. An Overshoot can take many forms, either hitting the wrong target, blowing something up, or simply adding a dangerous element to an otherwise successful spell. If you gain more control successes than Power successes, they do nothing special.

If the number of paired successes is greater than the required number for the spell, each additional success (called Special Effect successes) can be spent on one small precision effect. These can make a spell more powerful, affect larger or multiple targets, or do something cool.

NOTE: You can choose to spend a point of Control rather than rolling Control. Doing so counts as an auto-match of however many successes there were on your Power roll.

NOTE: If your countable Power successes are less than the target number for the spell, you may choose to spend points of Power to make up the difference. However, when your current Power level reaches 0, you are Magically Exhausted and will not be able to cast again until you have rested and regained your energy.

Here is a helpful table explaining Success Pairs.

Comparison Result
# PowerSucc > # ControlSucc Overshoot
# PowerSucc =< # ControlSucc All Power Succ are counted


Bean wants to cast Serpensortia, which is a Second Year spell. Bean has 4 Power and 4 Control. Bean is a Third Year.

Bean rolls Power vs 6
3 7 7 3 (2 Successes)

Bean rolls Control vs 10
8 4 10 9 (1 Success)

Bean's PowerSucc (2) is higher than his ControlSucc (1), so Bean Overshoots on his spell. This can look like Seamus Finnigan trying to turn his pumpkin juice into rum (boom!) but any cosmetic effect appropriate for the attempted spell is totally fine. (In a PRP, this is almost always decided by the Storyteller, but in general RP is up to the player in question.)

Let's say Bean wants to try again.

Bean rolls Power vs 6
8 6 4 8 (3 Successes)

Bean spends 1 point of Control. (Because he has 4 dots of Control, he can do this 4 times before he must rest or regain his energy.)

This means that Bean has 3 usable successes. Serpensortia (as a Second Year Slytherin spell) requires 2 successes. This means that Bean's spell is successful and he has 1 Special Effect success - he can choose 1 small bonus effect the spell wouldn't otherwise cover. He chooses to use that 1 Special Effect success to make the resulting snake look like his favorite kind - a Pinto Python.


Each dot in a School represents a -1 difficulty to the Control roll for magic that falls inside that School.


Bean is now a Sixth Year with an OWL in Charms. His Power is still 4, but he's practiced magic a lot and has increased his Control to 6. He wants to cast Serpensortia (which is a Charm) again.

Bean rolls Power vs 6
10 5 6 9 (3 Successes)

Bean rolls Control vs 9
3 6 9 6 2 9 (2 Successes)

Bean overshoots again, but he gets closer than he did before achieving OWL proficiency in Charms. Additionally, the number of Power/Control Success pairs does meet the spell success threshold. There's simply extra power on top that he's not in great control of. Most likely, he conjures a bigger snake than he really wanted to - or perhaps the snake is a silly color that makes it less scary than he meant it to be.

Example 2:

Bean is now an adult with an OWL, a NEWT, and some post-school job training in Charms (3 dots in that school). His Power is still 4, and his Control is still 6. He's going to try and cast Serpensortia one last time.

Bean rolls Power vs 6
7 1 6 6 (2 Successes)

Bean rolls Control vs 7
8 6 2 1 10 8 (2 Successes)

Bean's PowerSucc is equal to his ControlSucc, so all 2 successes are good. Serpensortia is a Second Year spell, requiring 2 successes. Bean doesn't get to choose anything extra, but the spell works as intended.

In Practice

Functionally, this system means that casting successful magic for most students is going to be a lot of spending Control points until they gain knowledge and practice that makes their Control rolls easier. This is okay! Casting magic is like any other skill - it wears you out when you're learning, when you're building the right 'muscles' to make it easier.

Overshooting is also not always a bad thing. If you overshoot Lumos, you've perhaps turned on the Magical HiBeams. If you overshoot Reducto you might blast a whole bookshelf instead of just that one desk. If you overshoot Reparo on a desk your Housemate just blew up, you might end up with a brand new desk rather than one that looks the same age as its fellows. Some magic requires serious precision. Others… not so much, so long as you can be flexible. Each character is going to have their own individual style and that's perfectly okay!

Additionally, we do not require that rolls are made for every single instance of magic used. Spells that are at least a year behind your current level and do not affect another PC should almost always be handwaved successful - especially in a purely social scene. If someone in a scene is uncomfortable with handwaving a spell, the roll should be made, but be reasonable about this. The focus of this game is cooperative storytelling. If an agreement cannot be reached, staff may be called upon to mediate and resolve the situation.

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