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Put a -1/-1 counter on target creature, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
The state-based action that removes matching +1/+1 and -1/-1 counters won’t check until after you proliferate and Grim Affliction finishes resolving. It’s possible to remove up to two +1/+1 counters from the creature by choosing to put a second -1/-1 counter on the creature when proliferating.
You may choose the creature you put the -1/-1 counter on to get another -1/-1 counter when proliferating.
