Spell Level

Every spell has a level from 0 to 10. A spell’s level is a general indicator of how powerful it is, with the lowly (but still impressive) magic missile at 1st level and the earth-shaking wish at 9th. Cantrips (simple, but powerful spells that characters can cast almost by rote) are level 0. The higher a spell’s level, the higher that the level of the spellcaster must be to use that spell.

Spell level and character level do not correspond directly to one another. A character must be at least 17th level, not merely 9th level, to cast a 9th-level spell.

Furthermore, in order to be able to cast a spell, your ability score in the spellcasting ability must be equal or higher than 10 + the spell’s level.

High-Level Spells

Spells of 6th level and above are high-level spells. The magic of such spells is particularly potent and the act of casting them is taxing on both the body and mind.

Each day, if you are capable of casting high-level spells, you may cast one spell of each spell level above 5th without consequences. That is, one 6th level spell, one 7th level spell, one 8th level spell, one 9th level spell and one 10th level spell.

Overcasting

If you cast more than one spell of 6th level or higher without taking long rest in between, the stress of casting weakens you. This is known as overcasting. Upon overcasting and thereafter, each time that you cast a spell you take one die of necrotic damage per level of the spell that you are casting. The size of the damage die is determined by the level of the spell that you overcast, as described in the Overcasting Damage table. This damage can’t be reduced or prevented in any way. When you finish a long rest you recover from the strain of overcasting and may once more cast spells without taking further damage.

Overcasting Damage

Spell Level	Damage
6th	1d4
7th	1d6
8th	1d8
9th	1d10
10th	1d12

For example, if a wizard casts two 6th level spells in a day and then later the same day casts a 3rd level spell, they take 3d4 necrotic damage.