"Don't use the Fronts rules (in the next chapter) for the first session either."
Wow. I read that chapter twice and totally missed that line.

I notice a lot of mention of leading questions. Should that be stuff like "You stand before the steel door of the Vault. What lies behind it?" or "You hear skittering in the darkness. What creature of the vaults do you fear the most?"

And thanks for the responses, guys. It feels like I should know this stuff, but you are being really helpful. I think I'll go back and RTFM again.

I might be GMing a game of Dungeon World soon, so I thought I might post what I have planned to see if it is enough or too much or too little. I didn't make a full adventure or campaign front because I want to see how the first session plays out first. My players really like Ocean's 11 style bank-robbing capers, so I though I'd start out with something like that. I'll be posting about how the session goes if I can get a group together.
The Setup
The Vaults of the Bat-King contain the (probably empty) tomb of Hematophagous Rex, vampiric monarch, erstwhile demigod, and alleged dinosaur.
This however, is of secondary concern to my players, as the Vaults also contain the King’s Ransom, which consists of the incalculable sums of gold and magical items Hematophagous Rex’ worshippers used to bribe Death, so that their deity and king might be restored to life.
The Situation
There is a whole bunch of money at the bottom of the Vaults. The party is at the top. In between, the living worshippers of Bat-King, his undead minions, and rival grave-robbers stand in the way. The Vaults have three primary sections: the Chiropteran Cathedral, a functioning place of (militant) worship dedicated to the Bat-King; The City Subterranean, a necropolis filled with the animated remains of Hematophagous Rex’ hierophants and priests; and, finally, the Vaults Proper, guarded by the servants of Death and containing the incredibly valuable King’s Ransom
Danger: Humbleblood, Larcenous Sorcerer and Aspirant Demigod
“I would love to stay and chat, but I have relics to steal and people to smite. Divinity puts such a damper on one’s social life.”
Type: Arcane Enemy- Power-Mad Wizard
Impulse: to steal the King’s Ransom (and to use the wealth and artifacts therein to acquire followers)
Impending Doom: Tyranny
Humbleblood uses the King’s Ransom to acquire worshippers and a temple, thus completing the final step to godhead. (Also, the party loses out on a metric ton of gold.)
Grim Portents:
•   The party does not detect Humbleblood
•   Humbleblood acquires the key to the Ransom Chamber
•   Humbleblood escapes from the Vaults with the King’s Ransom
Filled in Spaces on the Map
The Chiropteran Cathedral
   Worshippers of the Bat-King are big on basalt and obsidian. Statues of men and bats and things in between line the walls of the Cathedral. The Cathedral is filled with worshippers and members of holy orders at all hours, though many retire to their ceiling-hammocks in the Atrium and Basement when the sun rises. The knights and priests of Hematophagous Rex will fight to the death, though worshippers can be reasoned with. The entry to the rest of the Vaults is in the Basement, but is obstructed by a magical seal.
The City Subterranean
   An entire underground city populated by the shambling remains of Hematophagous Rex’ deceased priests. The city itself is bowl shaped, consisting of a series of tiered circles. Most of the undead will react with hostility towards the party and are not  intelligent enough to be bargained with, but there are a (very) few who are willing and able to parley. At the bottom is a pit, which leads straight down into the Vaults Proper. Located somewhere in the City are:
Hundregore: a lich of considerable power. Willing to bargain with the party. Will teach a druid or anyone who can cast spells (including through multiclass stuff) to summon and control a certain spirit. I am still working on how the move will work, but I am thinking something a la the wizard’s Summon from World of Dungeons.
Mikhail Sergeyev: a vampire thrown into the City Subterranean by Chiropteran priests. He will pass on his…condition to an ambitious (or stupid) adventurer, provided they provide him with a way to escape the city. Rather nasty in a fight. Will flee if wounded.
The Vaults Proper
   The King’s Ransom is locked behind an adamant gate, which requires a key to open. The key is actually in the Vaults Proper—not due to design, but because an ancient grave-robber brought there before perishing. His body and they key are in one of the Vaults’ many twisting side passages. Hematophagous Rex quite literally paid for his unlife, and so Death guards his bribe jealously. In addition to various creatures from the Land of the Dead, there are two Concept Elementals. One is a Manifestation of Decay; the other is an Incarnation of Entropy. I am hoping my players surprise me with a way to bypass them, but I think I’ll say they can be negated through the presence of a spirit who governs an opposing sphere.

I haven’t quite figured out what the treasure will be.

@samuraiko
Thanks for the advice! I've pretty much only ever played 4e, and I spent some time looking over Old School Revival Stuff, so I'm still getting used to a more free-form play-style. One thing I wasn't clear on in my first post, though—I'm pretty sure as long as a Druid has a whale shape and Chimera, they can turn into a giant monster by grafting on other animal bits. So the creature in question was actually a blue whale with scorpion body parts.