Donal, Herald of Wings | Cloudstone Curio | Palinchron

Cards

Palinchron in hand.
Donal and
Cloudstone Curio on the battlefield.
You control up to seven lands that can tap to produce at least ({4} magic symbol) ({U} magic symbol) ({U} magic symbol) .
You have not copied a spell with
Donal this turn.
({5} magic symbol) ({U} magic symbol) ({U} magic symbol) available.

Cast
Palinchron by paying ({5} magic symbol) ({U} magic symbol) ({U} magic symbol) .
Donal triggers, creating a copy of the
Palinchron spell that is a 1/1 Spirit in addition to its other types.
The copy of
Palinchron enters the battlefield, triggering itself and
Cloudstone Curio.
Resolve the
Palinchron trigger, untapping up to seven lands that can tap to produce at least ({4} magic symbol) ({U} magic symbol) ({U} magic symbol) .
Resolve the
Cloudstone Curio trigger, returning
Donal from the battlefield to your hand.
Activate seven lands by tapping them, adding at least ({4} magic symbol) ({U} magic symbol) ({U} magic symbol) .
Resolve the original
Palinchron spell from step 1.
Palinchron enters the battlefield, triggering itself and
Cloudstone Curio.
Resolve the
Palinchron trigger, untapping up to seven lands that can tap to produce ({4} magic symbol) ({U} magic symbol) ({U} magic symbol) .
Resolve the
Cloudstone Curio trigger, choosing not to return anything to your hand.
Cast
Donal by paying ({2} magic symbol) ({U} magic symbol) ({U} magic symbol) .
Donal enters the battlefield, triggering
Cloudstone Curio, returning
Palinchron from the battlefield to your hand.
Activate seven lands by tapping them, adding at least ({4} magic symbol) ({U} magic symbol) ({U} magic symbol) .
Repeat.