At first, it is where 9Dragons moves away drastically from other MMORPGs featuring the tank/heal mechanic. The 9D healer is not a healer in the traditional sense, and is not supposed to heal a party while staring at health bars. And incidentially, the class is not able to do that. So, forget for a moment what your priest/cleric/monk did in your previous game, and read on.

As is known to all the Healer class is the true support class, and primarily, through BUFFS. Your buffs, if leveled up, are second to none, and make a big difference. Actually, they are sorely needed to get the best exp/hour. Therefore this class will probably not be for you if you mind buffing people. The healing aspect is a totally different beast. The heals are mostly Heal-over-time spells, and touch range. The latter fact makes it virtually impossible to heal an entire group that doesnt stand close together. It also means you will draw unwanted attention of the mobs for you basically run into the fray. Also, heals arrive slowly, level slowly, and heal slowly.... only at the very end of your skill selection are there direct heals, and the only true heal in the eyes of a mainstream MMO player is on a 30 minute cooldown, making it more of an emergency button.

At the same time, there are extremely few healers around, partially due to the fact that you will spend a LOT of time levelling your skills. Almost all skills you raise just by fighting are not important to the class, and attributes almost exclusively matter for fighting. The Buffs and Heals are all a matter of levelld skills, so the class plays very high-maintenance.