Slime Serpent!

So, you want a fancy new Slime Serpent mount? Set your Dungeon Difficulty to Heroic, get yourself prepared with as many mobility/self-heal tools as you can manage, make sure you’re NOT in a party with anyone (or the mount won’t be available), and head into the Plaguefall dungeon. Once inside, head down the hill to the first fork in the path.

Take the left path, and hug the hill in the center. There are a couple of patrolling Plagueborers to avoid, and a Plagueroc on top of the hill.

You can’t skip the Decaying Flesh Giant; it sees through stealth, invisibility potions, and any other trickery you might employ. Just kill it, interrupt Creepy Crawlers (unless you LIKE spiders), and dodge the Toxic Pools.

This is Globgrog’s room. You won’t be fighting him. Head through the poison on the right side of the room, taking care not to pull any of the little oozes or the Plaguebelcher. If you DO pull the Plaguebelcher, kill it quickly, as it gets stronger each time it successfully absorbs oozes from Beckon Slime.

Another fork in the road. Head left, avoiding the Plagueroc at the bottom. Hug the left wall and run as far forward as you can.

This is where you’ll end up. You want to cross the slime pool and head onto the path on the left; there’s a patrolling Blighted Spinebreaker to avoid (or not, it’s your decision. I can’t be responsible for EVERY choice you make).

This part is annoying. Exploding Rigged Plagueborers will constantly spawn and run in from the far side of the pool, and there are multiple Slime Tentacles that can’t be avoided. I skip the first tentacle and hug the right wall, working my way around. You’ll pull the last two tentacles, but they’re not a big deal (unless you get both at once, then you’ll take a LOT of poison damage).

Killing this guy (Virulax Blightweaver, if you’re one for formalities) will stop the mad bombers from spawning. If you can lure him close to the Unstable Canisters on the right and cleave them down, they’ll remove nearly 75% of his HP when they explode (this is going to be nerfed in 9.1, I believe).

This is Doctor Ickus’ arena. You won’t be fighting him either. Hop on a mount, run around the right sides of the two islands on the right, and go up the stairs. If you accidentally pull anything, I’d try to kite them to the stairs before fighting, as you risk pulling Ickus if you remain on an island.

Mount up again, hop into the slime river on the left side, run between the mound on the left and the island in the center, and cross to the nice dry path on the far side.

You’ll be spending some time here. A Brood Ambusher awaits you at the bottom of the hill, along with two trash packs you need to clear. I usually kill the Ambushers first (interrupting their Enveloping Webbing cast), then the Venomous Snipers (they summon large spiders), then the Defender of Many Eyes (stun them out of Bulwark of Maldraxxus if you can). That little slime cove on the right is where you’ll get your Slime Serpent at the end of this ordeal. At the far end of the platform is a stealthed mob trying to pick a lock. That’s the boss, Domina Venomblade: she can’t be skipped and she can be pretty difficult. Here’s a quick rundown of what to expect:

• She summons for Brood Assassins at regular intervals. They hide in large puddles of webbing (Shroudwebs) and constantly shoot you with Assassinate, so you need reveal all of them by running through the webs then kill them ASAP. Mobility-enhancing tools are your friend.
• She will periodically stun you for three seconds with Shadow Ambush. Keep defensive CDs handy, especially if there are adds up.
• Cytotoxic Slash is a thing, but it’s not much to worry about.

If, I mean, WHEN you defeat Domina, head through the door that she was attempting to lockpick before you rudely attacked her.

Jump into the large hole in the floor and cross the slime pool, killing the two Plaguebound Devoted that are waiting for you (they melee HARD, so watch out). If you look to your left, you’ll see this teleporter in an alcove: it’s your way back to the surface once the last boss is dead.

This is Margrave Stradama’s lair. There are three packs of Plaguebound Devoteds and a named mob, Ickor Bileflesh. Head to the pack on the left, staying far enough from Ickor’s trash pack to avoid pulling them, and kill the two packs in the back before dealing with Bileflesh. You can pull him first, but he’ll Ghost Step between the trash packs until they’re dead if you do, which can be annoying and time-consuming. Once Ickor is dead, back away from the pool in the center of the room so you can pull Margrave Stradama on your own terms.

Stradama is intimidating, but I found her to be easier to defeat than Domina. Here are the basics:

• Prioritize Malignant Spawns as they, uh, spawn. You’ll want to soak every Touch of Slime circle to avoid taking massive damage. Unless your DPS is really good, you won’t have much uptime on the boss between spawns; AoE and cleaving attacks are useful here.
• Stradama will submerge at 66% and 33% health, at which times you’ll need to dodge several Plague Crashes. Don’t stand in front of the tentacles when they turn yellow, and you’ll survive.
• After she emerges a second time, she’ll stay on the surface until killed, casting Plague Crash now and then. This is where you would use Drums/Heroism/Bloodlust if you were doing this in a group. Finish her!

After you defeat the slimy Margrave and claim your awesome loot (/chuckle), head back topside using the teleporter I pointed out earlier. Go to that alcove on the side of Domina’s platform, and a Curious Slime Serpent will be swimming in the ooze. Give it a friendly pet (you’ll have to stand in the slime and might pull that big Plague Belcher), and the Slime Serpent will be yours! Enjoy!

Full disclosure: I did this as a Protection Warrior with an average item level of 218. Some of my key tools were:

• Gluttonous Spike, for some passive healing and AoE DPS
• Blood-Spattered Scale, for a decent panic button paired with an AoE burst
• Bounding Stride, for enhanced mobility during the Domina Venomblade fight