From the limited selection of online RTS games this one is fairly engaging...

User Rating: 6.5 | World of Battles: Morningstar PC
This is your pretty typical run of the mill fantasy RTS. You level up as you go through multiplayer battles and complete the single player challenges (which are pretty repetitive). I was expecting some base building but this game is more Total War then Command and Conquer. You start with an army and upgrade your legions as you increase your XP and make money. The battles are pretty standard stuff but are still fun as you always fight with two or more allies (all human players). After a while it can become pretty boring but as long as you don't expel your enthusiasm by playing it for more then a solid hour during each sitting your likely to want to come back for more. There is nothing here revolutionary and the style of RTS is old skool. You have spells and such like to improve your chances on the battlefield and importantly, it's really easy to get into. It's all pretty self explanatory so if your looking for a game that doesn't require a field manual, is quick and easy fun and provides some progression (and obviously you need to be a RTS fan), then you'd probably enjoy this game. If your looking for complex development and deep RTS then this is certainly not the game for you. And it's free to play!