Deadmines is one of the dungeons that has undergone updates after the Shattering. Among some of the chances include the removal of undead enemies such as Ghouls and Skeletons, and the new inclusion of Hobolins, Kobolds and Ogres. There are also five new quests for both Alliance and Horde parties that traverse this dungeon for the first time.
The bosses themselves have also been changed, with only one previous remaining. The first, Glubtok is an Ogre Mage that casts both fire and ice type spells and can drop a decent dagger once killed. Second boss on the list is Helix Gearbreaker, a Goblin that rides on top of a large Lumbering Oaf. After the Oaf is killed, Helix will randomly jump on top of party members and throw bombs around the room. It is the job of the "ridden" player to move themselves and Helix out of the way of these area effect explosions so that the damage dealers can finish the enemy.
The third boss of Deadmines is Foe Reaper 5000, a giant Harvest Golem with some nasty area attacks. To make maters worse, this boss will sometimes ignore aggro and attack non-tanks for 10 or more seconds. It is possible to attack the smaller Harvest Golems and mount them once they take enough damage. This will allow anyone to take control of them for a short time and use them to fight directly with the Reaper. He may drop a one handed sword, staff and/or hammer when defeated. The fourth boss is Admiral Ripsnarl, a Worgen in Ironclad Cove. He mostly fights with single target damage but can add in knockdown attacks. The final boss for the normal version of the dungeon is Cookie, a murloc from the earlier version of the Deadmines. He is immobile during the fight, making it easy to target this boss. He will throw food at the party, some that will buff attack and movement, while others will debuff. It's easier to just ignore these items and just attack Cookie directly.
For those on Heroic, there is one last enemy to fight: Vanessa VanCleef. However, you won't be fighting right off the bat. You'll have to move through a room of fire and take down Glubtok a second time. Next, Helix will attack again but will be supported by a huge number of spiders, but it's once again to take down the Goblin and ignore his helpers. A second round with the Reaper will take place, however, you must avoid or destroy several spark walls along the way. Next, you'll need to save several NPCs from Worgen attacks. They can be directly healed, so it's not really a hassle to worry about the damage they are taking.
Upon reaching the top of the boat again, you'll finally fight Vanessa. She isn't tough on her own, opting to enhance her parry and dodge skills rather than try to damage you. However, she will call in many helpers to keep you busy. After taking enough damage, Vanessa will set charges and you need to grab on various ropes to swing to safety. If a party members fails to escape in time, the explosive charge will be enough to one shot them. If you're a healing class that can rez, be sure to survive the blast so that you can help anyone that missed the escape. Vanessa will set these charges several more times as her health gets lower, so be on the lookout for the ropes each time.