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Each creature you control that's a Wolf or a Werewolf enters the battlefield with an additional +1/+1 counter on it.
[−2]: Create a 2/2 green Wolf creature token.
A creature that’s a Wolf or Werewolf enters the battlefield with one +1/+1 counter if it would otherwise enter with no +1/+1 counters.
A creature that’s both a Wolf and a Werewolf receives only one additional +1/+1 counter from Arlinn’s ability.
If Arlinn leaves the battlefield before her last ability resolves, most likely because she only had 2 loyalty when you activated the ability, the Wolf token won’t enter the battlefield with a +1/+1 counter.
