Meow-Meow-Mu is a Link-1 monster, meaning all you need is a single Level 4 or lower Prank-Kids monster to summon it, which can then allow you to activate your Prank-Kids Main Deck monster's effect and continue to Link climb
P/T Number 177 Language English Legal Formats Brawl, Commander, Competitive Brawl, Historic, Legacy, Modern, Pioneer, Timeless, Vintage Not Legal Formats Alchemy, Pauper, Standard Rulings (8/7/2020) If you don't cast the nonland card with mana value 3 or less, it'll be put on the bottom of your library in a random order with the other cards
The ongoing effect of that early bit of filtering is immense and has made magic a significantly better game as a result
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