Sorcerer Spellcasting
Your bloodline provides you with incredible magical power. You are a spellcaster and can cast spells using the Cast a Spell activity. The tradition from which your spells come is determined by your bloodline. As a sorcerer, you draw your power from within, and the gestures and incantations you use to shape your power might evoke the nature of your bloodline. For instance, a sorcerer with a demonic bloodline might chant guttural fiendish phrases or make brief curt gestures to cast a spell.
Each day, you can cast up to three 1st-rank spells. You must know spells to cast them, and you learn them via the spell repertoire class feature. The number of spells you can cast each day is called your spell slots.
As you increase in level as a sorcerer, your number of spells per day increases, as does the highest rank of spells you can cast, as shown on the Sorcerer Spells per Day table.
Some of your spells require you to attempt a spell attack to see how effective they are, or have your enemies roll against your spell DC (typically by attempting a saving throw). Since your key attribute is Charisma, your spell attack modifier and spell DC use your Charisma modifier.
Heightening Spells
When you get spell slots of 2nd rank and higher, you can fill those slots with stronger versions of lower-rank spells. This increases the spell's rank, heightening it to match the spell slot. You must have a spell in your spell repertoire at the rank you want to cast it in order to heighten it to that rank. Many spells have specific improvements when they are heightened to certain ranks. The signature spells class feature lets you heighten certain spells freely.
Cantrips
Some of your spells are cantrips. A cantrip is a special type of spell that doesn't use spell slots. You can cast a cantrip at will, any number of times per day. A cantrip is always automatically heightened to half your level rounded up—this is usually equal to the highest rank of sorcerer spell slot you have. For example, as a 1st-level sorcerer, your cantrips are 1st-rank spells, and as a 5th-level sorcerer, your cantrips are 3rd-rank spells.