Almost

Taming Tags.

Formerly, they were the signature item of the Tamer class. However, a few months ago the developers added the Beast-Master sub-class to the Druid, Ranger, and Barbarian classes. It was available to some Paladins as well, but the ones who actually took it were so few it was eventually patched out to just those three. But, by enrolling in that sub-class, the player could use a Taming Tag to tame one creature as an Animal Companion. The Tamer Class was still used, especially since that same update boosted their abilities, and raised the number of companions they could keep, but it wasn't long before many new players started walking around towns with Animal Companions of their own.

Just as the bitch is about to snap the collar on you, you manage to get out of the way.

"Too Close," you think.

You whip around and swing your new Ax of the Undying at your opponent, catching her in the back.

"GAH!" she screams, as she falls to the ground. You give her no chance to recover and follow up your blow with a swift kick to her torso. You knock her into the air, and she lands on her back a few feet away, her HP in the low double digits.

You stalk over to her and heft your ax to deliver the final blow. But as you do, your eyes fall on the Taming Tag that still sits unused in her hand. As far as you know, the item doesn't have a level restriction, it's just more practical to use it on a lower level creature so you can control how it develops. The only creatures immune to it are bosses (the first time you saw a Tamer try and catch your late mother with one was... well, let's just say you wish you had a camera to record the event). As you look it over, and idea creeps into your mind. Perhaps it is time for a bit of poetic justice.