http://www.joymax.com/dmo/
Game is Free to Play with a cash shop. So far, I've been enjoying it, graphics aren't bad, seems to have a thriving community since they recently added another server. Lots of Digimon of course.
I think one of my fav parts right now is you can customize what you're Digimon can say for certain things. Like when mine get's low on Digi-Soul (Mana basically), I have him say "We require more Vespan Ga-I mean, Digi-Soul!" cause I'm a dork like that lol.
Beginning of the game lets you choose from 4 tamers to basically look like, and then 4 starting Digimon: Agumon (newer one, not the classic one), Falcomon, Lalamon, and Gaomon. There's 2 worlds, the Real World and the Digital World. You can find Digieggs and hatch them into Digimon, tho it's a bit of a pain cause of how the system works. You gotta get "mats" for the egg to incubate with, and what's required differs a bit between each egg. You have to put the data in a minimum of 3x in order to hatch the egg, but it goes up to 5x, with the digimon being bigger and stronger if you can do it. Catch is, you can break the egg and it's a 50% chance every time you put data in sadly. Haven't been able to get a Betamon yet cause of this, gone thru 3 eggs right now. If you get frustrated, the cash show does sell eggs that guarantee at least the 3/5, with a chance for 4/5 or 5/5. I got my Guilmon from the shop and got a 4/5, so not too bad.
The beginning tutorials are very helpful, tho I figured out the egg thing on my own cause somehow I missed that tutorial for a while lol (is was in an area I forgot to do a quest in).
The music in the game is surprisingly good (and I think one song is a remixed Pokemon theme LOL).
Digivolving is based on level and the Tamer's Digi-Soul (Mana). You get rookies as your partner, and when they reach level 11, they can digivolve to their Champion form. How long they can stay in that form (or Ultimate or Mega) depends on the Tamer's DS. The skills the Digimon can use change depending on form and level, and they use the Digimon's own DS.
You can also ride certain Digimon once trained (I saw someone riding a Gigaseadramon, was pretty awesome!).
I'm still fairly new to the game and still learning things. I believe there are dungeons and raids too, as well as real-time events (like the rifts in Rift or some of the events in GW2).
You can get clothes for your tamer too and change how they look. Mine's pretty simple right now since I don't have much.
If you guys start playing, I'm on the Beezlemon server (new one). My Tamer is named Liel. Here's a couple of screens of my Guilmon/Growlmon, Noble.
(If you can't read his speech bubble, it says "Squirrel!")
). There are so many FTP games out I'm not sure what one I want to play more! Neverwinter has consumed my life for the past 2 days but I will give this one some time too 
