I'm hoping some of you can check out our logs and give some advice. We've been on Thok for a few weeks now, and while we've had some success, our main problem is consistency. We've had a few sub 10% wipes, but they are few and far between.
There are usually early deaths in the stack phase, or during fixates. We've recently started with a new kiting strategy, so fixate deaths shouldn't be a problem anymore.
BrM Monk (w/dps OS)
Blood Dk (w/ dps OS)
Fury Warrior (w/ alt Hunter)
Ret Paladin (w/ tank OS)
Ele Shaman (w/ resto OS)
Our BrM solo tanks, and our Ele Sham has been healing due to absences. Unfortunately we've been 4 melee/2 range for a good chunk of attempts, causing bats to be a problem. We usually end the first phase around 25 stacks - 65% - 60% on boss health. 10 stacks during fixate, and transition into bats. Personals and Bloodlust around 3 or 4 during Poison and everyone focuses bats. We usually transition between 7-10 stacks, but have wiped quite often at this point. When we do succeed, we do another 10 stacks during fixate and repeat our CD rotation during frost. We make it to Fire phase with boss health ~15%, but our lack of experience in this phase has been a problem.
Our CD usage looks something like this, but will vary based on who's available:
5 / Ret BoP Priest Spirit Shell
8/9 - Ret BoP Druid Tranquility
13/14 Ret Devo- Holy Pally CD
17 - Smoke Bomb
18 - Holy Pally Devo
20 - Power Word: Barrier, (stack until we phase usually 22-24 screech)
Honestly, 60-65% in first stack phase with no lust is fine. Your main issue is that you are solo tanking it with heavy melee (which is not really great for bat killing, as you said yourself). For bats, you'll have ele shaman cds (get hpally to BOP him for AG as a raid CD during AOE), fury warrior CDS, and rogue CDS. We actually went 2 tanks for this exact reason, and it was a lot easier (we had 2x ranged, 4x melee aswell, if I recall correct).
As for the fire phase, it's extremely simple. Have the entire raid stacked up on a mark on the side of the boss. Your tank then slowly rotates the boss clockwise or anti clockwise, and the raid simply follows, to avoid standing in the fire. You'll phase fairly quickly when you run out of CDS due to being stacked, but that's how it is - if he's at 15% when you enter fire, he'll easily be in kill range during the last kite phase (and you get smoke bomb and warrior cds, so should be able to last to about 10 stacks in fire phase still).
I'm a little confused to your actual setup because its swopping so much.
You have had a disc in called Torab who is decent but then recently you have one in called Sera who is not very good at all. If Sera is a regular then theres plenty of things he / she can be doing to drastically improve healing and help you get to 28-29 stacks consistently.
You holy paladin is also doing really badly.
It's probably because I just woke up and I'm grumpy and critical but you've been wiping on this for 3 weeks and theres basics that these guys aren't even managing to do right. These are from your 25th April attempts.
1) Hes taking divine purpose. A proc based ability. Damage on Thok is predictable, it starts low and gets higher and higher until you break a phase. With that in mind, Holy avenger is probably the single biggest throughput cooldown he has but he chose DP.. NEVER use DP as holy, use holy avenger.
2) Holy pala has 4 healing cooldowns, avenging wrath (wings), GoAK, Divine favour and HA. He only uses wings. That's 3 healing CD's hes completely ignoring.
3) Hes using glyph of avenging wrath. It's useless.
4) He never uses personal CD's outside of bubble (Divine protection)
5) Flasking helps
6) Holy shock should be used on cooldown to generate holy power to make people better, in a 4 min attempt he used it 22 times. It could have been used closer to 40 so that's about 50% efficiency.
1) Divine star for this fight is so OP it should almost be considred cheating. Your disc priest chooses to use halo. I don't even... Regardless, some tips on divine star. Consume archangel stacks for "moar power" > screech > divine star. You can get 2 off under archangel if ur quick which makes them stronger.
2) I'll tie this in to the 5^^ ret BoP spirit shell etc. Spirit shell usage is awful. It healed 540k in a 4 min attempt. Theres no need to BoP so early, screeches aren't constant by 5 and inner focus can prevent the interrupt. Once again archangel > inner focus > SS > PoH
3) Archangel uptime is bad (22%). Disc should revolve around getting those stacks and consuming them for more healing oomph.
4) Almost never uses prayer of mending. Not an amazing spell but its instant and it jumps, perfect for a fight where people are being interrupted the whole time.
5) Hes using the healing cloak, most discs use the dps one because the healing proc is shit for disc and the dps cloak has oodles of delicious crit.
Anyway, the tl'dr is on the attempts of the 25th you were getting no where because the healing was terrible. The above stuff is just a holy / disc 101, its not what you should be pointing out to people who have been stuck on the same heroic boss for weeks.
How we did it for the first time was with a solo tank (Brewmaster), 4 healers same as your comp actually (Druid, Pally, Priest, and Shaman). We would do the stack phase till about 26-27 rotating cds devos bops tranqs shaman things etc. The kite phase we did to about 13 so that all our cds would be back for the next stack phase. When bats came out we would hero second pots etc, if you have extra bop you can throw it at a good ranged aoe dps (shaman, lock) to help bats die faster. By keeping all the phases on the long side we actually didn't even see the fire phase. Since the first kill we have done this with pally tank, and also a dk tank.
It looks like you're not using all of the CDs you have available during the stacking phases. I'm not seeing Rallying Cry, Demo Banner, or HTT. Don't bother with BoPing the priest at 5 stacks, the damage is not too intense at that point yet. Instead, have your warrior use both Rallying and Demo after the 6th stack. Is smoke bomb effective on this fight? It's not going to reach both groups so I'm wondering how you're using it. Instead, I would suggest using HTT at around 16 stacks, this will carry you into 20+ and with barrier you should be able to push 25+.
Now, as for the bats. Emphasize, then emphasize again, that everyone needs to have all of their major DPS cooldowns/2nd potion available for when the bats come out. You need to be able to kill the bats within 15 seconds after they come out. As soon as your tank gets aggro, BoP the elemental and have him chain lighting with AG. This will make healing for this part fairly trivial. Also, if you're saving smoke bomb from P1, have the rogue drop it on the melee here.
Now, the change that made the bat phase night/day for us was a proper stun rotation when they get below 35%. The reason bats are a pain is because not only do they heal themselves, but they do so while putting out a tremendous amount of raid damage. If they're stunned, they can't do either. So, as soon as the tank has the bats all clumped up, BoP the shaman, drop smoke bomb on the melee after a couple seconds, then have the warrior shockwave followed by a warlock shadowfury when the bats are below 35%. With heroism, they should melt.
After the bats are dead, the fight kind of becomes auto-pilot. There are no new major mechanics, and you're essentially just repeating the same thing you did for the first phases. The only thing that can wipe you at this point is people messing up kiting and/or the yeti hitting someone not paying attention.