It Puts Counters on the Creature If Slime Against Humanity left its Ooze at 0/0, it would immediately die and the spell would be worthless, so it puts a number of +1/+1 counters on that creature equal to two plus the total number of cards you own in exile and in your graveyard that are Oozes or are named Slime Against Humanity
Its hard removal, not your typical Fiend Hunter effect, making it a versatile summon
Especially if you have more than two colors
If Frodo, Adventurous Hobbit and Sam, Loyal Attendant are your commanders, your deck may contain cards with white, black, and/or green in their color identity, but not blue or red
Even partners with inherent synergies or partners that are dependent on each other contribute to this problem
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