You have cast at least one instant and/or sorcery this turn.
({1} magic symbol) ({U} magic symbol) available.
Steps
Cast any spell, or wait for an opponent to cast one.
Holding priority, cast Memory Lapse either from your hand or from the top of your library by paying ({1} magic symbol) ({U} magic symbol) , targeting that spell.
Elsha, Thousand-Year Storm and Storm-Kiln Artist trigger.
Resolve the Elsha trigger, giving it +1/+1 until end of turn.
Resolve the Storm-Kiln Artist trigger, creating a Treasure token.
Resolve the Thousand-Year Storm trigger, creating at least one copy of Memory Lapse, with each copy targeting the original Memory Lapse.
Storm-Kiln Artist triggers for each copy made this way, creating at least one Treasure token.
Resolve the first copy of Memory Lapse, countering the original Memory Lapse and putting it on top of your library.
All remaining copies of Memory Lapse fizzle due to having no legal target.
Activate two Treasures by tapping and sacrificing them, adding ({1} magic symbol) ({U} magic symbol) .