First, identify a proven deck archetype
Helm of the Ghastlord, Ophidian Eye, and Curiosity all turn Y'shtola, Night's Blessed into a relentless engine, drawing cards and draining life every time you sling a spell
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Online resources like EDHREC are perfect for finding powerful, popular cards you might've otherwise missed, but it's also great to go completely off-piste, figuring out different interactions between niche cards, and building something that's entirely your own
While Master Ball Foils also appear in this set's English twin, Prismatic Evolutions, their standing as one of the most desirable variations gives this Umbreon the edge over its Special Art Rare twin