Essential Packs for Core Meiru Cards:
* The Sacred Cards: Contains Meiru Hen, The Black Bird, Meiru Shou, The Blue Jay, Meiru Asuka, The Red Dragon, and Meiru Falcon. These are the main boss monsters of the Meiru archetype.
* Ancient Prophecy: Contains Meiru Fowl, Meiru Wolf, Meiru Snake, Meiru Stag, and Meiru Rabbit. These are important Level 4 monsters used to summon the bosses.
* Ancient Sanctuary: Contains Meiru Guardian, Meiru Guardian, Meiru Guardian, and Meiru Guardian. These are Level 3 Meirus you can use for your Ritual Spells.
* Hidden Arsenal 4: Abyss of the Relentless: Contains Meiru Guardian, Meiru Guardian, Meiru Guardian, and Meiru Guardian. More important Level 3 Meirus to build your Ritual Engine.
Additional Packs for Support Cards:
* Cybernetic Horizon: Contains Meiru Falcon - Silver Wing, a powerful new addition to the Meiru archetype.
* Legendary Duelists: Immortal Destiny: Contains The Sanctuary of the Bird, a Ritual Spell that can be used to summon multiple Meiru monsters in one turn.
* Other booster packs: Look out for cards that can enhance your Ritual summoning strategy or provide additional support for Meiru monsters, like "Mystical Space Typhoon", "Twin Twisters", and "Heavy Storm Duster".
Remember:
* Meiru cards are not very common in booster packs. You'll need to open many packs to find the cards you need.
* Consider buying singles online if you want to build your Meiru deck more efficiently and save money.
* The Meiru archetype has not been updated in a while. You may need to experiment with different cards to find the best build for your playstyle.
Good luck building your Meiru deck!