Donal triggers, creating a copy of the Peregrine Drake spell that is a 1/1 Spirit in addition to its other types.
The copy of Peregrine Drake enters the battlefield, triggering itself and Cloudstone Curio.
Resolve the Peregrine Drake trigger, untapping up to five lands that can tap to produce at least ({3} magic symbol) ({U} magic symbol) ({U} magic symbol) .
Resolve the Cloudstone Curio trigger, returning Donal from the battlefield to your hand.
Activate five lands by tapping them, adding at least ({3} magic symbol) ({U} magic symbol) ({U} magic symbol) .
Resolve the original Peregrine Drake spell from step 1.
Peregrine Drake enters the battlefield, triggering itself and Cloudstone Curio.
Resolve the Peregrine Drake trigger, untapping up to five lands that can tap to produce ({3} magic symbol) ({U} magic symbol) ({U} magic symbol) .
Resolve the Cloudstone Curio trigger, choosing not to return anything to your hand.