The caster assumes an incorporeal state, not unlike a ghost, able to freely pass through objects and rendered totally immune to physical damage. They cannot interact physically with the material world except by sight and speech.
Ingredients: A mirror.
Process: The caster spills their Blood on the mirror, chanting, and then breaks it.
System: Make a Ritual roll. If the roll is a win, the caster assumes an incorporeal form as long as they hold a shard of the broken mirror. While incorporeal, the caster remains immune to everything except fire, sunlight, and arcane weapons and rituals capable of damaging spirits. The caster can still be seen and heard but cannot interact physically with anything or anyone. They cannot Rouse the Blood while incorporeal. Incorporeal casters have no access to any spirit realm; the ritual does not make them wraiths or spirits. The caster can walk through walls and other objects but must do so in a straight line; they cannot change direction while inside solid matter. This Ritual lasts for one scene or until the caster drops the shard. Returning to the material while inside solid matter can result in anything from destruction to entombment to minor inconvenience (the ashtray is stuck halfway through the caster’s arm); the Storyteller decides the precise outcome.