Counters Cancel Out
Judge Level 1+1/+1 meets -1/-1 — and both vanish without anyone being able to react.
Cards involved
The setup
Your Grizzly Bears carry a +1/+1 counter (3/3), next to them your Llanowar Elves (1/1). Your opponent controls a Fume Spitter.
The Spitter sacrifices itself
Your opponent sacrifices the Fume Spitter (a cost — it's gone immediately): put a -1/-1 counter on target creature. Target: the Bears.
What happens?
The ability resolves.
The Bears now have a +1/+1 and a -1/-1 counter. What happens?
Pick an answer to continue.
The SBA cleans up counter pairs automatically (704.5q) — nobody can "respond", because SBAs run before anyone receives priority. The difference matters: effects like "remove a counter from …" find nothing afterwards.
704.5qIf a permanent has both a +1/+1 counter and a -1/-1 counter on it, N +1/+1 and N -1/-1 counters are removed from it, where N is the smaller of the number of +1/+1 and -1/-1 counters on it.
And the Elves?
Had your opponent chosen the 1/1 Elves instead: 0/0 — the SBA puts them into the graveyard immediately (704.5f). Again: no response window. There is no "in response to the dying" with state-based actions.
704.5fIf a creature has toughness 0 or less, it’s put into its owner’s graveyard. Regeneration can’t replace this event.
Stack
Grizzly Bears
Your Bears — with a +1/+1 counter (3/3)
Llanowar Elves
Your 1/1 Elves
Fume Spitter
Sacrifice: put a -1/-1 counter on a creature
Activated ability: Fume Spitter
Fume Spitter ability — target: the Bears
The stack is empty.
Battlefield
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