Rappelz

Site: http://rappelz.gpotato.com/
Free-to-play, with in-game shop

Rappelz is a free-to-play Korean MMORPG. The action is staged on a fantasy world. Main game features are the player-ownable dungeons, pet system, rideable mounts. The players can choose from three races Gaia, Deva and Asura.
The pet system is quite well developed with the ability to level up, evolve and overbreed pets.
Classes:
Deva are holy-based race, they have healing magic and defensive buffs.
Deva can choose from three jobs: Holy Warrior(defense fighters, tank), Cleric(buffs and heals) or Breeder(pet heals and buffs).
Gaia - they focus on natural magic and heavy melee combat. For first job players can choose from fighter, kahuna or spell singer.
Fighters can choose two paths for advance - to use heavy melee weapons or range attack(bow).
Kahuna(Gaia magician) have melee skills, combat support buffs and direct damage magical attack.
Spellsinger have buffs that work both on them and on their pets.
Asura specialize on evasion, attacks and damage magic. The options for the first job are Strider, Dark Magician and Sorcerer.
Striders are the damage dealers in a party. They either specialize in dual daggers, swords or crossbows.
Dark Magicians have direct damage spells, area of effect spells, curses and buffs.
Sorcerer(Asura Summoner)have buffs to improve their pets' combat abilities.
Remarkable stuff:
Stamina System - players gain bonus for staying online or if having a tent.
The socketing system(uses soul stones to improve equipment)
Also the game has standard PvP and PK system a lot alike many other Korean MMORPGS.
Dungeons are ownable by player guilds. They can be obtained through dungeon sieges.