A 3/4 Flying Haste for 5 with Firebreathing is not that impressive, but Cosmic Sovereign also spawns another temporary body with Haste at the beginning of each combat
Flying commanders like Ganax, Astral Hunter and Lulu, Loyal Hollyphant only need a few swings for you to win via combat damage with Raised by Giants as their background
// Haste As you put one of Summon: Magus Sisters's chapter abilities on the stack, you choose a mode at random
An already strong offensive Pokmon that can instantly buff your whole team and help you win the game twice as fast, it's hardly surprising this card became so popular for so long
Eight mana for a 6/6, even one with Hexproof, is a dire rate these days
Wave 1 (identifiable by a blue bottom on the box) was the initial, lower-volume run