Aika -- developed by HanbitSoft and JoyImpact and published via the gPotato portal -- recently held a big PvP event that turned out to be a smash hit with the community. There's a short video showcasing some of the action, which you can find after the break. It's short, but there's a lot going on so a second or third viewing may be a worthwhile idea.
The large PvP battles and city siege features of Akia help it to stand out amongst the ever growing crowd of free-to-play titles, but don't take our word for it because open beta is right around the corner. We'll be interested to see what the wider MMO community thinks of the game.