Yes, Hero: 108 is a Cartoon Network show with a Samurai Jack/Powerpuff Girls art style. It was actually developed by Phoenix Tarng of Gamania who is making the Hero: 108 Online MMO. It’s based on a 14th century Chinese novel where humans and animals are struggling for peace.

Long ago in The Hidden Kingdom, animals and humans lived together in peace... until the evil HighRoller convinced the animals that humans were their enemies. HighRoller and his animal armies mistreat the humans and drive them from their homes. But there is hope, thanks to a rebel force of young heroes. This team of heroes live in a giant abandoned turtle shell called “Big Green” and fight HighRoller to protect the humans and restore peace in the Hidden Kingdom.
The game on the other hand, is based on the most generic and boring facets of every MMORPG ever made. It consists of going from NPC to NPC gaining new quests that generally require you to grind, grind and grind. Kill 10 of this, grab 10 of these, get the picture?
Yes, the graphics are ultra-cool in the aforementioned heavy outline Samurai Jack or Powerpuff Girls fashion and the sound is pretty decent as well. The game really does have some fantastic
2.5D graphics. You should at least load it up and check them out. But the gameplay is flat and consists of everything I hate about MMOs. It’s as if they took some generic Make-an-MMO program and slapped their graphics on it and that was that.
It’s a shame when a brand new IP has a chance to do something different and instead falls into the rut of all that have gone before. Even though the game is free-to-play online I can only ask "why would you?" There are far better and more interesting games out there to put your time into.
In one night of play, just a couple hours, I’ve reached level 17. Some skills improved, I got some better equipment and I’ve killed a lot of mobs. In fact, there are multiple quests which have you kill the same mob, first 10, then 15, maybe 20, etc.
The game is far from interesting aside from the look. I haven’t seen the cartoon but if it’s anything like the game then I expect it to be extremely formulaic and each episode to follow the intro - problem - struggle - solution formula and there to be very little in the way of interesting story or any type of continuity to say the least.