mtg wall cards Poster Whenever Wall of Souls is dealt combat damage Subtype: wall, Colors: Green, 19

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And later, when Doctor Doom was revealed, the hosts lingered on the note about how Doom is indestructible as long as the player controls an artifact creature...or a "Plan." Rasmussen then revealed "Doom Reigns Supreme," an Enchantment card with the subtype Plan that collects a plan counter whenever a Villain enters

Yes, there is less variety in terms of the card combinations, but realistically, given that you have over 30 years of cards to pull from for the format, even mono-colored decks have plenty of win conditions and strategies to pursue

I would argue that every time you combine two or more cards, it is designed to gain an advantage over the opponent at least if you try to win the game