Ravenous Slime 2G Creature Ooze 1/1 Ravenous Slime can't be blocked by creatures with power 2 or less
Wrenn and Six [Most Efficient Two-Mana Planeswalker] Discussions about the best planeswalker always end up circling back to Wrenn and Six, usually followed by someone saying, Its only two mana. Yes, and thats the problem
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And in my opinion, its been a long time coming: Fantasy environments are full of magical books of all power levels, from the most mundane spells to forbidden, powerful arcane knowledge
If the creature can't attack any of those players but could otherwise attack, it must attack a planeswalker an opponent controls, a battle an opponent protects, or the player that goaded it