If you really wanted to cover all the bases, you could add 9 more cards that, according to my research, are rarely but occasionally played competitively these days: Arrogant Wurm, Beetleback Chief, Bottle Gnomes, Fyndhorn Elves, Order of Leitbur, Order of the Ebon Hand, Portent, Shield Sphere, and Whispers of the Muse
Just like Chaos End Master, these are monsters that can serve as restricted additional copies of Sanctum and Ignition
Each attempts balance (which can be derailed by chance card draws, opponent attacks, and other factors) although they all play differently
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