Cho’Gall, 25 man Bastion of Twilight
Cho’Gall has three phases, the first two alternating back and forth. In phase one your raid will stack up and dispel. Phase two will see you spreading out, interrupting and dispelling, killing adds, and killing boss. The third phase is all about focusing and burning down. With practice this fight is easily downed.
This boss will give you an insanity meter, which each member of the raid will need to keep an eye on individually. In all honesty, this can be used as a good measure to see how much raid awareness each person has. With each thing that hits you/you stand in, your meter will rise. Every stack you get of insanity, you increase the damage you take by 3% in phase three. Every 25% you will see new penalties for these infringements.
25% Corruption – Accelerated: This accelerates your stacks, you will want to focus on dispelling this. Unfortunately it will not clear the insane stacks themselves.
50% Corruption – Sickness: Causes you to vomit on players in front of you, increasing their insanity stacks as well. You need to stand just outside of the stack and face away from the raid.
75% Corruption – Malformation: Will spawn a hostile tentacle out of you.
100% Corruption – Absolute: Increases the damage done by you by 100%, and spells are also instant. Reduces healing against you by 100%
Start off by stacking DIRECTLY on top of each other at the front of the circle once the trash is cleared. Have your two primary tanks pull Cho’Gall and face him away from the raid. One of the first things the raid will notice is Conversion. Boss mods will show this also as “Worshiping”. Three raid members (in 25 man) will be chosen at random and become mind controlled, and increase his damage by 10% each. It’s important to break this control as soon as possible as the longer they are controlled, the more their insanity will stack. This can be broken with Warstomp, Shadowfury, or less optimally Fear, Scatter Shot, and Shockwave.
Cho’Gall summons the aid of elementals during this first phase as well. Flame Orders will summon a fire elemental, who will cause the tanks to take additional damage. Along with this, it will also summon circles of fire on the ground called Blaze. Don’t stand in the fire, nothing new. Tanks will also see an increase in the damage they take during Flame Orders. Cho’Gall will also summon a shadow elemental with Shadow Orders, the raid will see more damage with this elemental. Your healers may want to adjust accordingly.
The tanks are not without their own mechanics on this fight, Fury of Cho’Gall is designed just for them. We have our two primary tanks stay on the boss for the whole fight and just switch this mechanic back and forth. Fury causes massive physical and shadow damage and increases the damage the afflicted tank takes. So change tanks when one gets this debuff.
Cho’Gall will summon an extra add, this is the Corrupted Adherent. It will appear from a portal and should be picked up as it spawns, we have a Death Knight go Blood for this task. The add will target a random raid member and give them a swirly purple pattern where they stand called Corrupting Crash. You and your raid have seconds after this is cast to scatter away from the spot. Even better, move early. It will cast several of these, so watch for the phase to end before stacking up again, and watch to make sure you move if one targets you or someone near you. Getting hit with this will greatly increase your insanity. It is possible, and in fact likely, that you will have Blaze and Corrupting Crash to deal with at the same time. Stack up again as soon as the crashes are done. All focus should go into bringing it down quickly. The add will cast a spell called Depravity, which should be interrupted by any means. Once the add is down to about 30%, have the offtank kite him to the entrance. Range will need to continue dpsing and interrupting him. 30 seconds after the Adherent is spawned, Cho’Gall will cast Fester Blood. If the add is still alive, it will receive a massive buff. If its dead, a pool will form, and from that pool will spawn adds called Corrupted Blood. Slow these, AoE these, knock these back (yes elementals, you can unglyph Thunderstorm for this fight!). Kill them and keep them out of the raid, if they hit someone, that person will take a hit to their insanity.
Cho’Gall will go into phase three when he hits 25%, you should start moving him to the wall prior to this. Ideally when going in to phase three, it’s hoped that no one will be above 25% of their insanity meter. The reality in a 25 man is that this will likely not be the case. So again through the phase, dispellers should be aware of anyone who hits the 25% mark and dispel the Accelerated Corruption, and everyone should be conscious of their own meters to turn from the raid if they hit 50% for Sickness Corruption.
In phase three, the constant monitoring of one’s self and surroundings (although still important to be mindful of Sickness Corruption) is replaced with the frantic need to kill. Cho’Gall needs to be brought to the wall for this phase. He will spawn tentacles in this phase, if placed right you should get three groups of these: left, right, and on top of him. The tentacles will choose a target and cast a beam on them, this beam will reduce the damage the target causes and the healing they receive by 75%. Interrupt the beams and dps the tentacles down as quickly as possible. Dps should switch between dpsing these tentacles, and dpsing the boss. Do this til Cho’Gall hits zero hp and win!