Ninrō

Ninrō (忍狼) are essentially wolfs that have heightened senses and abilities, and as such, are able to work alongside shinobi.

Well trained ninrō have shown the ability to use human language, walk on water, develop combat strategies, and track down targets through their enhanced smell. They are supposed to be quite dangerous in combat, and able to combine techniques with shinobis.

It is not uncommon for a shinobi to be able to can summon more than one ninrō separately or all together. Mangetsugakure is currently the village with more ninrō per person. Garō clan is known for combat alongside ninrō, as well as train and sell them as ninja invocations. It's said that a pack of eight to ten ninrō are more than enough to take over a small village.