Make sure you get the Seattle 1998 version, which uses the original art
They can be used to block almost any card, from creatures to sorceries to artifacts to planeswalkers, so long as you have them ready to catch those cards in the exact moment an opponent tries to play them
It also increases the likelihood of them connecting thanks to its second ability, which can dole out Deathtouch at the cost of three mana
By the way, I don't know if you noticed, but the modern Oracle wordings for the ten dual lands has what they tap for in reminder text, so they are, technically, according to the same wording as Urborg, Tomb of Yawgmoth, now fully colorless
I also love that it says spell, so this includes all your nonland cards
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