The Rotface encounter is more of a dance then anything, the boss doesn't have a lot of health so your dps should be able to focus on doing things right over seeing how high they can get their dps. As you can see in the video above we chose to 2 heal this fight which makes things a bit tuffer on us so if your just learning the fight I suggest you 3 heal it. Damage will be pretty light on the raid in general unless people aren't getting out of the way of his spit up, but if people are having troubles with that then they probably shouldn't be in your raid he turns him self around its easy to see easy to avoid.

As for the tanks the main tank will be taking quite a bit of damage as usual but nothing to over stress, the tank you have to watch out for is the off tank that'll be kiting the oozes. If he gets too close to the ooze he will be hit really hard really quick so preferably you would want a death knight off tank for this fight because they have lots of range abilities to hold agro. However in the video above we have a warrior off tank and a hunter using misdirection to help him keep the agro of the big ooze. The only other members that should be taking damage are the people with the infection on them, it does quite a bit of damage before cleansed and even when cleansed the small ooze will be hitting that person until it is merged with the big ooze.

There are two things you will have to watch for with the unstable ooze explosion is that you all want to be stacked up close to each other and on the opposite side of the boss as the main tank, do not break until the oozes are in the air and then everyone run out and not in the direction of the main tank. You do not have to run far to avoid damage from these so get back in and close quick after they have hit the ground.

When you get the infection you must run out of the party and have it cleansed off you, similar to the grobbulus encounter in Naxx, however this time you drop a slime and your problems do not end when you drop it. That little ooze starts out with a lot of agro on you and is immune to taunts, so its your responsibility to keep that ooze away from the raid and get it merged with a big ooze before you go back to the fight. The reason it is a good idea to have 3 healers on this fight if you don't know it well yet is if one or both of you gets it, unless you are very familiar with the fight you will have a hard time healing while you drop off your ooze.

You also might have noticed in my video the quarters of the room filling with ooze (If you didn't, don't feel bad, just make an appointment with your optometrist). This does a lot of damage and slows you down so watch out for them when your playing with your small oozes, an easy way to tell if one is about to spawn near you is that the pipes near it will start spitting slime before it floods the room.

The Rotface encounter really wasn't that different and is probably the easiest Heroic boss to do after you get through the first 4. In addition to having more health and doing more damage he now uses Vile Gas which you will recognize from the Festergut challenge. So you just have to do everything the same way you did in regular mode but you can no longer stand near the boss. This means you get to dance around the floor floods, slime puddles, oozes, and make sure you know where to run when he uses Unstable Ooze Explosion.