I thought about building a four-color deck using Atraxa, Grand Unifier or Atraxa, Praetors Voice, which gives us access to blue and two pretty powerful commanders, but after a quick Scryfall search, there were only three blue explore cards I thought would be worth adding: Subterranean Schooner, Deepfathom Echo, and Nicanzil, Current Conductor, none of which I think are good enough to add a fourth color, especially in a budget deck
Draft Booster The sibling to the Set Booster packs, Draft Boosters were the other pack type replaced by Play Boosters
Sea Basin Beast Kyogre Fish/Effect/WATER/Level 8 ATK 2800/DEF 2500 You can banish 3 WATER monsters from your GY
Why is Preordain so good
(too much Japanese names already?) [spoiler=Ame-no-Nuhoko''] Activate by revealing 1 Spirit monster from your hand: Normal Summon it in addition to your Normal Summon or Set this turn without any Tributes and equip it with this card