One thing Mabinogi has which is very fun is the ability to play as your pet. He can’t do all that much, because he is a pet-no talking to NPCs, for example. But just the ability to run around as an ostrich, gigantic bear, or sheep is a fun gameplay quirk.
My own pet is a sheep. Part of trying the MMO was browsing the cash shop, and it was just such an absurd pet I had to have it. Well, between the sheep and the cow, but the sheep won out. I think that’s part of what sold me on the game, that it was willing to give players that kind of choice in pets outside of combat. Sheeparix can heal, but he can’t fight to save his life. He’s just white, wooly moral support.