Rappelz

Rappelz is a free 3D MMORPG set in a medieval world that features three races (Deva, Asura and Gaia), three classes, and five sub-classes where over 5 million players adventure and battle in a dark and devastated fantasy world.

With a guild siege system, Rappels enables its player to own dungeons rather than castles or cities. To assist in combat, a strategy of pet is also available. Rappelz provides a good learning guide to those who have the access to pet taming and summoning skills.

Rappelz is great for people who really like pets. It provides them with a unique tactical pet taming & training, extensive player-versus-player and player-versus-environment gameplay, with huge player base.