If you are a spellcaster, you may expend MP to cause harm instead of casting a spell you know. This is called a maleficence. Such physical manifestations of your power take on a shape and form unique to you as a spellcaster.
Rolling for Maleficence
You may expend 1 MP to conjure magical energy and cause harm to a single target within a melee space, instead of casting a spell. Roll a d6 and add your Smart vs. the target's defense: this is called a maleficence attack. (You may add a +2 if you have any Arcana skill.) Your magic manifests as a destructive force that is released as the type of energy you chose at character creation. If your attack is successful, you deal 1d6 volatile damage and inflict the maleficence's peril on your target.
Perils & Secondary Effects
Each maleficence inflicts a minor peril and a secondary effect.
For example, the cold maleficence's peril slows victims:
Mechanically, this means the peril confers the status effect slow on the target. The status effect lasts until after victim's next action, unless the maleficence says otherwise.
In addition to this, maleficence has a secondary effect on the environment: the cold maleficence in particular "freezes liquids." The secondary effect of a maleficence is purposefully vague so that it is open to interpretation by the GM and creative input from the players.
Some abilities allow you to use maleficence in conjunction with another attack (such as the Paladin's Sacred Touch ability). In this case, use the attack's damage instead of the volatile damage of the maleficence. Moreover, instead of a maleficence check, use the weapon's attack vs. the victim's defense. If you hit, deal the weapon's damage, and inflict the peril of the maleficence. If you miss, the target takes no damage and you do not inflict the peril of the maleficence.