Wicked Wolf
Creature — Wolf
When this creature enters, it fights up to one target creature you don't control.
Sacrifice a Food: Put a +1/+1 counter on this creature. It gains indestructible until end of turn. Tap it.
Illustrated by
Throne of Eldraine#181RareEnglishLegality
Rulings
You can activate Wicked Wolf's last ability even if it's already tapped.
If the target creature is an illegal target when Wicked Wolf's first ability tries to resolve, the ability doesn't resolve. If Wicked Wolf is no longer on the battlefield, the target creature won't deal or be dealt damage.
You can activate Wicked Wolf's last ability any number of times while its first ability is on the stack.
If an effect refers to a Food, it means any Food artifact, not just a Food artifact token. For example, you can sacrifice Tough Cookie (an Artifact Creature — Food Golem) to activate Maraleaf Rider's ability (an ability with "Sacrifice a Food" in its cost).