This creature enters with a +1/+1 counter on it.
Whenever a creature you control with a +1/+1 counter on it becomes the target of a spell an opponent controls, create a 1/1 green Insect creature token.
, : Put a +1/+1 counter on this creature.
(25/09/2020)
An ability that triggers when a creature becomes the target of a spell resolves before the spell that caused it to trigger. It resolves even if that spell is countered.
(25/09/2020)
You create just one Insect token, no matter how many +1/+1 counters the target creature has on it.
(25/09/2020)
If a spell targets a creature you control with a +1/+1 counter on it more than once, Swarm Shambler’s ability triggers only once.
(25/09/2020)
If a creature without a +1/+1 counter on it becomes the target of a spell an opponent controls, putting a +1/+1 counter on it after that won’t cause Swarm Shambler’s middle ability to trigger.
