Kukini, Ali'i Runner

Haste
Whenever Kukini, Ali'i Runner enters the battlefield or attacks, you may exile target artifact card from your hand face down. If you do, at the beginning of your next upkeep, you may cast that card without paying its mana cost.
Kukini can’t be blocked by creatures with power 3 or greater.
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"From Waipi'o to Kona by nightfall — no path too rough, no valley too deep."