From Udon Entertainment:
When Mara Shin’s dog Toto gets lost one fateful day, she follows his trail along some yellow brick road and ends up in the wonderful land of Oz! Everyone instantly starts calling her Dorothy, but these aren’t the cowardly lion, brainless scarecrow and heartless tin man adventures you remember. This fantastic fairy tale features familiar characters…but with a definite action/animated twist!

A classic redone for new fans. Met Mara Shin a ordinary student whose life was normal until one day she chase after her dog Toto. That when she saw the yellow brick leading her to Oz. There thing are not the same Oz that we know. Colons, Robots, and Chimeras oh my. So join Mara (Dorothy), Abbe (Scarecrow), Namu (Tin Woodsman), and Tail (Cowardly Lion) down this twist adventurer down the yellow brick road.

From Tokyopop:

In real life, Roto, Boromid and Ah-Dol are average kids with average problems, but in the virtual world of Lost Saga, they're heroes. They might even become legends... if they can stop bickering long enough to level up. Whether it's werewolves running rampant or a gorgeous pair of troublesome thieves, our boys must be ready for anything, because in Lost Saga nothing is what it seems and murder can happen with a click of a mouse.

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The series centers on the main character Jang-Gun and his friends along with their virtual reality avatars in the computer game world called "Lost Saga". When Jang-Gun logs on as a different character, he "Creates" an AI with a personality from the hacked disk he found when renewing his appearance for his once a year renewal process. Yureka is a flutter-brained, but advanced, AI with powerful stats and a real-life doppelganger. It is his turn to see just how deep his immersion in the virtual world goes.