Casting Time

Most spells require one or two actions to cast, but some spells require much more time to cast.

Some spells are triggered by an action on your turn. If you have multiple spells active (for example, two spiritual weapons), then a single casting of a spell may only be triggered once per round.

Longer Casting Times

Certain spells (including spells cast as rituals) require more time to cast: minutes, or even hours. When you are attacked while casting, there is a possibility that this may interrupt the spell, as described under the Sustain a Spell action. If your spellcasting is interrupted, then any mana spent is lost. If you want to try casting the spell again, then you must start from the beginning and spend the mana again.