This loop is a masterclass in recursive tempo, turning Selvala, Heart of the Wilds and a cheap creature into an infinite engine with the help of Hullbreaker Horror's devastating cast triggers. While Tannuk, Steadfast Second hangs back to grant your team haste and warp flexibility, it's the Horror that does the heavy lifting: every time you cast a spell, its triggered ability bounces your other permanents back to your hand. By alternating the casts of Selvala and your other creature, Hullbreaker Horror continuously picks up whichever one just hit the battlefield so you can recast it. Meanwhile, Selvala taps for massive amounts of mana to fund the entire operation, easily sustaining the loop while generating infinite storm count, creature enter-the-battlefield triggers, and colored mana.