Jorn, God of Winter // Kaldring, the Rimestaff | Moritte of the Frost | Lithoform Engine

Cards

Moritte of the Frost in hand.
Jorn and
Lithoform Engine on the battlefield.
Jorn does not have summoning sickness.
Snow permanents you control can tap to produce at least ({3} magic symbol) .
({2} magic symbol) ({G} magic symbol) ({U} magic symbol) ({U} magic symbol) available.

Cast
Moritte by paying ({2} magic symbol) ({G} magic symbol) ({U} magic symbol) ({U} magic symbol) , having it enter as a copy of
Lithoform Engine.
Put
Lithoform Engine into your graveyard due to the legend rule.
Declare
Jorn as an attacker, triggering its ability.
Holding priority, activate all mana producing snow permanents you control by tapping them, adding at least ({3} magic symbol) .
Activate
Moritte's first ability by paying ({2} magic symbol) and tapping it, copying
Jorn's triggered ability.
Resolve the copy of
Jorn's ability, untapping all snow permanents you control.
Repeat from step 4.