The Japanese 1 EDITION mark is a different design composed of a large 1 and the letters EDITION. While the mark is on the bottom of the card, its position is not uniform across eras and card layouts
While the 3-cost range is strong, its actually the 1, 2, and 4-cost ranges that stand out the most in this deck, allowing players to get more characters into the action early and then boost their forces in the mid-range game
60 damage for two Grass Energy on a Stage-2 monster wouldnt normally be impressive, but its attack gets a massive bump up to 130 damage when facing ex opponents
Many Commander decks are multicoloured and synergistic, so its easy to convert them into a strong, recognisable draft archetype
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Legality depends on the tournament format -- Sporesower Thallid can be legal in some formats and banned or restricted in others