Cataclysm Heroics.

Blackrock Caverns
Rom'ogg Bonecrusher:
Casts Quake, move out of dust clouds which spawn adds, kill adds. Casts 'Chains of Woe' and 'Skullcracker' combo, dpsers have to DPS down Chains of Woe (it's a targettable, much like Illhoof in Kara) and run away from the boss to avoid being one shotted.

Corla:
Casts Dark Command, a fear, interrupt or dispel it. Purple beams flow from the dragon above your heads to the Zealots kneeling in front of her. Use as many ranged as you can to block the beams from reaching the Zealots by standing in between the Zealots and the beams. Beams place a stacking debuff on whoever it is currently hitting. Move out of beam when you get to ~80 stacks, move out to drop stacks and allow the Zealot to get 80 stacks, move back in immediately. 100 stacks = MC player/Evolved Zealot.

Karsh Steelbender(optional):
Starts with 90% damage reduction. Has to be pulled through the lava stream to be able to deal damage to him. When pulled through the lava stream, he loses the damage reduction buff and gains the damage taken increment buff. Each stack gives him 5% extra damage taken. The stacks last for around 6-8 seconds and gains one or two stacks at a time by pulling him through the lava every so often. For every tick he is in the lava he will cast an AoE, the higher his debuff stack, the harder the AoE hits. When the debuff drops, elementals spawn on the outside and have to be pulled to the bottom of the ramp and killed there. Use a DPS with Taunt-like abilities if available. Drops lava pools on their deaths, when boss is placed in said lava pools, it emulates him being placed in the lava stream.

Beauty (optional):
Use as many Beast CCs as you can on the three puppies in front of her. Don't kill Runty (he does not engage with the rest of the group, he will enrage the boss when killed). Kill any remaining puppies, they place lava pools on the floor, get away from them. Kill boss.

Ascendant Lord Obsidius:
Three adds that need to be kited/OTed throughout the fight. They place healing debuffs on the kiter/OT if they are close enough. At 66% and 33% the boss will switch places with one of the adds. Pick him up quickly and burn him down.

Deadmines
Glubtok:
Tank and spank till 50%. After 50%, he is untankable, and he will spawn a moving Fire Wall with him as the center of the Fire Wall. Melee needs to watch out for this. He will also spawn adds and drop icicles. Tank adds, avoid stuff, burn boss.

Helix Gearbreaker:
Avoid bombs. Don't bother killing the minions. When he jumps off the Oaf and attaches himself to one of the players, just keep attacking the Oaf. He will also attach bombs to someone's chest, that person has to run away. The oaf will also pick up someone and charge into the wall with him, heal him up. After Oaf is dead, kill the goblin.

Foe Reaper 5000:
Avoid Overdrive (whirlwind). Casts harvest which targets a random player and places a mark on the floor. Get out of his path and the mark, it will one shot you. Someone needs to get on the Prototype vehicle to tank the Fire Elementals which spawn near the boss's starting area. Just spam 1, 1, 2. Advised to tank the boss on the ramps. Enrages at 30%.

Admiral Ripsnarl:
DPS down vapors then focus on boss. Last 500k health or so he will spawn 3 vapors at once. Ignore and kill him.

"Captain" Cookie:
Rotten food leave an AoE on the floor and when ingested will place one stack of a DoT on you. Eat good food to remove one stack of the DoT. Keep DPSing boss. Untankable. Tank can go DPS spec for this fight. Feel free to use a paladin to bubble and eat up all the rotten food.

Vanessa VanCleef:
Very long.
First phase: Click levers to escape. Wait for fires to spawn. Stay away from fires and ice patches. Boss is at the end of the ramp. Tank and spank.
Second phase: Boss spawns at the first boss' location. Tank him near the corner just to the side of the door. Spider adds will spawn. Ignore and burn boss.
Third phase: Lots of moving Electrical Walls, avoid and make your way to the end where the boss is waiting. Tank and spank.
Fourth phase: Tank the three worgens which are attacking the NPCs. They periodically go back to attacking the NPC so it's pretty much a DPS race. Run to the next NPC and save him, run to the boss, burn him down before he kills the NPC.
Fifth phase: Kill adds, kill boss. Ropes spawn opposite of where the ramps leading to the ship are. Click to avoid being one shot by the fires. When you swing back to the ship, the boss will not engage till you attack her. Take your time to recover mana/CDs.

Grim Batol
General Umbriss:
If you have a CC for Humanoids, excellent. Boss summons Troggs to aid him. There is one special Trogg that spawns called the Malignant Trogg. If killed, he will transform any normal Trogg within his range into a Malignant Trogg as well. If the boss is near him when killed, he will gain a 50% damage increase. The Malignant Trogg is CCable, and if CCed, the boss will not spawn any more Malignant Trogg until the current one dies.

Forgemaster Throngus:
When he picks up his shield, stay away from the front of him. When he picks up his Mace, do not stand in lava pools and kite him. Someone will also be impaled. Heal him up. When he picks up his Dual Swords, expect heavy incoming damage and just tank him as normal.

Drahga Shadowburner:
Run away from Fire Elementals if you are targeted by one. They will target you with a fire beam. DPS boss down to 50%, he hops on a dragon and continues to summon Fire Elementals. The dragon will also periodically cast a breath (Devouring Flames) which is quite large. Stay away from it.

Erudax:
Targets a random player with a snare, just keep running when he targets you with it and you will avoid it. Casts Shadow Gale, get in the dark spot he spawns to avoid damage. Once Shadow Gale is over he spawns two Guardians. Move out of the eye with around 2 seconds remaining on Shadow Gale to run to the door and wait for the Guardians. Split your DPS accordingly with slows to kill the Guardians. They will attempt to reach the eggs and spawn whelps which deal damage to everyone in the party and cannot be killed. He will also periodically place a three second debuff on the tank and knock him back. The debuff increases damage taken by 100%. Keep away from the boss until the debuff is gone.

Halls of Origination
Temple Guardian Anhuur:
Stay out of fire. The boss will periodically place a shield up and start channeling a spell that places a stacking DoT on everyone. Levers to deactivate the shield spawn on the left and right pillars in the sand pit below and have a 10 second channel. Have everyone except one DPS with an interrupt jump down. Place someone on lever duty and have the tank pick up all the snakes as they interrupt the channel. Once both levers are pushed the shield will deactivate and the DPS that was left up top should interrupt him immediately.

Earthrager Ptah:
Stay out of spikes that first appear as dust clouds on the floor. Boss breaks apart at 50%, adds spawn. Kill adds. Avoid tornadoes and quicksand. Kill boss.

Anraphet:
Casts Alpha Beams which places void zones on the floor. These void patches remain for the whole fight, so very slowly kite him in one direction to avoid being overwhelmed. Casts Omega Stance which deals massive AoE damage. heal through it. Kill boss.

Isiset:
Damage her to 66%, she will will spawn three adds and disappear. Kill the Astral Rain first. She will reappear and disappear again at 33% health. Kill the Celestial Sky. She will reappear for the last time and then kill boss. Turn around when she casts Supernova. (Like Eadric)

Setesh:
Has no aggro table. Spawns portals which must be nuked immediately. First add to come out of the portal is the Void Sentinel which must be tanked till the end of the fight as they have a 75% damage reduction. Second add to spawn is a pair of Void Wyrms which must also be tanked. They can be killed by dragging them through the purple puddles that the boss creates on the floor. Third add to spawn (you really don't want this) is the Void Seekers which channel a debuff on their targets which makes their targets unable to cast or receive healing. Stay out of the purple puddles. Stay out of green dome AoE on the floor. He also spawns black crystals with a green aura which place a debuff on the player when popped by running over it. Debuff lasts for 20 seconds and allows the player to shoot a 18k+ bolt at his target when he damages something. Crucial to fight. Does not stack, so call out for someone to pick it up if you just picked one up. if it is too far from you, avoid it as it will be a DPS loss.

Zerging this boss is only an option if you have a good group.

Ammunae:
Kill podlings that spawn. They eventually mature into plants (you don't want this). If they do mature into plants, you can kill a Spore to leave a puddle on the floor which "rots plant life". The boss starts at 0 Energy. When he reaches 100 Energy he will cast an AoE. Interrupt Wither.

Rajh:
Interrupt spells. Stay out of fire tornadoes/fire trails. Stats at 100 Energy. Spells cost him Energy. When he reaches 0 Energy he will walk to the middle of the room and start dealing huge AoE damage to recover his Energy.

Lost City of the Tol'vir
General Husam:
Stay out of dust clouds and golden traps/circles. he also throws a random target into the pillar. Heal through it.

Lockmaw & Augh:
Stay away from whirlwind. Stay away from his tail. When you get Scent of Blood, stack on the tank. Kill the crocs. Kill the bigger croc. Enrages at 30%. Dispel Enrage if possible. Augh spawns after Lockmaw dies, and hits hard.

Augh can disorient a tank, which causes him to lose aggro. Dispel it with Magic. Stay out of whirlwind. Also enrages but is unable to be tranquilized.

High Prophet Barim:
Stay away from fire pillars. Kite away from Fire Phoenix. Stay out of fire. Keep DPS on boss. At 50% he rips your soul and transport you into another realm. Kill the Dark Phoenix while kiting it away from Soul Fragments. Soul Fragments can be slowed or stunned if you are having trouble with them. Kill boss.

Siamat:
Places a 90% damage reduction shield on himself while adds spawn. Kill adds. Once adds are dead the shield drops. He will then bounce everyone around for awhile. Try not to get knocked off the edge. You can use the Wind Tunnel if you get dropped. Smaller caster adds continue to spawn. Get melee to kill the caster adds. Also casts Gather Storm Cloud which deals AoE damage to all members.

Shadowfang Keep
Baron Ashbury:
Casts Pain and Suffering. Interrupt if possible, else dispel. Casts Mend Rotten Flesh. You must interrupt this. It heals him for 30%. Casts Asphyxiate. Brings everyone to 1 hp. Immediately casts Stay of Execution after. Every tick of Stay of Execution heals you and the boss for 10% health. Let it tick 1-2 times before interrupting as the heal will run out of mana pretty quickly otherwise.

Baron Silverlaine:
Two choices: Zerg boss, or DPS down adds then DPS boss. Your mileage may vary.

Commander Springvale:
Kill adds. Interrupt adds' Unholy Empowerment if possible. It heals him for 4%. Ranged should maintain distance from the Wailing Guards as they cast an AoE spell lock (Screams of the Past). Stay out of front of boss. Stay out of Desecration. After around the second wave of adds, he places Word of Shame on all players which decrements the player's health by 5% every 3 seconds. It is now a DPS race. Kill boss.

Lord Walden:
Casts Conjure Mystery Toxin. If you get the red debuff, stop moving. If you get the green debuff, keep moving. He also casts frost shards which are indicated by him shooting small little frost shards to small blue circles on the floor. Stay out of the circles.

Lord Godfrey:
DPS adds. Try and interrupt Cursed Bullet as best as you can. Stay out of the front of the boss when he casts Pistol Barrage (it's a cone), even the tank.

The Stonecore
Corborus:
Stay out of pink/purple shards. They explode and deal huge AoE and place a debuff on you that increases your damage taken. AoE the shards down. When the boss burrows, stay away from dust clouds. The boss will do a dolphin dive and one shot you. Kill rock elementals that spawn.

Slabhide:
Avoid dark shadows on the floor. Spikes will fall down from above and one shot you. Stay away from dust clouds, they spawn lava pools. When he casts Crystal Barrage LoS behind a spike that is out of his hit box.

Ozruk:
Casts Ground Slam which is a cone of spikes. One shots tank. Walk through his model when he casts it to avoid it. You can also choose to sidestep it. Casts Elementium Spike Shield. Whenever you melee him, you place a DoT on yourself. You want this. Also casts Elementium Bulwark. This reflects spells. This is spellstealable but only do so if your healer/ranged are far enough form the boss (20 - 30 yards). Casts Paralysis - Shatter combo. One shots everyone in range. He will cast Paralysis and the only way to break it is through dispel Magic or damage done to you. This is where the DoT comes in for melee. As soon as your Paralysis is broken run away from him.

High Priestess Azil:
Casts Gravity Well. Stay out of it. Summons adds. Hide behind the Gravity Wells so that the adds have to run through them, thus killing them. When she is on her pedestal she will throw boulders at you. Stay away from dust clouds. More adds will spawn. Kill boss.

The Vortex Pinnacle
Grand Vizier Ertan:
Everyone stack in the middle. Tank and spank.

Altairus:
Stay out of tornadoes. Always stay downwind. Gives haste buff.

Asaad:
Jump to avoid Static Cling. Also dispellable by Magic. Spread out (ranged) for chain lightning. When he casts a Temporary Grounding Field, get to it immediately. Supremacy of the Storms will be cast immediately after and is a one shot.

Throne of the Tides
Lady Naz'jar:
Stay out of spouts (white swirly things on the floor). At 66% and 33% she will place a shield on herself and summon three adds. Two casters and one melee. CC the casters if you can. DPS down the melee add then the casters. While she has her shield up she also summons water tornadoes. Stay out of it.

Commander Ulthok:
Places void zones on the ground in front of him which grow. Keep kiting him while maintaining high DPS on him.

Erunak Stonespeaker & Mindbender Ghur'sha:
Stay out of Earth spikes. Interrupt Lava Burst. DPS boss to 50% at which the octopus on his head will detach and MC another player. DPS the MCed player to 50% and he will pop off automatically and cast two abilities. Absorb Magic absorbs all healing done to your members and redirects the healing done to him. Purge it or spellsteal it. He also throws poison pools on the floor. Stay out of it. Rinse and repeat.

Ozumat:
Kill smallest adds. Kill small faceless mobs. Tank large faceless guardian. Once they are all down, four sappers will spawn and other adds will continue to spawn. DPS should just focus on the four sappers. Stay out of the black pools, they place a stacking DoT on you. Once the four sappers are down you will grow large and be able to attack Ozumat. At this point it becomes a DPS race and you should blow all cooldowns. Healers will not be able to keep you up for long. Killing the adds when you are large may give you more time to kill him if you are having trouble, otherwise kite them as they are easily kitable.

Please note that these tactics are posted pre-patch-whatevernumberitwas. Meaning, some bosses have had changes, which may not be here.