Mario and Luigi jump back into the warp pipe to Sirena Beach. They go there only to see that nothing is wrong.
Luigi: I guess we'll have to-a go in the hotel.
Mario: Right, Luigi.
Mario and Luigi run up to the manager.
Manager: Oh, thank goodness you're here! The hotel had to be closed down today!
Mario: What?!
Luigi: Why?!
Manager: Because of the creepy sounds coming from the basement! Can you go check it out?
Mario: Sure! We'll find-a the source of the sound, then we'll-a get rid of it!
Manager: Thank you, Mario Brothers. Right this way.
The manager leads Mario and Luigi into the casino. They can hear distant "BLEAH" and "HAHAHA" sounds.
Luigi: This is-a creepy!
Mario: The basement is the casino. Let's go there!
Mario and Luigi run up to the casino guy and talk to him.
Casino Guy: Oh! The manager has informed me of your arival! Right this way!
The Marios were led into the casino. When they got there, they saw people gambling and the sounds were a little louder.
Luigi: Mario, if the hotel is-a closed, why are there people down here?
Mario: Lots of people sneak into the casino at night! These are the guys who always blow all their money trying to get rich.
Luigi: Oh.
Mario: Let's investigate.
So Mario and Luigi take a look around.
Mario: Luigi! The sounds are louder around this-a giant roulette wheel!
Luigi is holding a large sack of coins and stuffing more from the slot machine inside.
Mario: Luigi?
Luigi: I got-a lucky!
Mario: Good! We may-a need those coins if we get-a hurt!
Luigi: Bravo Luigi!
Luigi fills his sack and drags it to the wheel. He and Mario pocket about ten coins.
Mario: Now-a where is that-a sound coming from?
Luigi: Mario! Look!
Luigi points to a purple section on the roulette wheel.
Mario: Good job-a Luigi! What is it?
FLUDD: Perhaps you should do a Ground Pound.
Mario: Nice-a thinking, FLUDD.
Mario ground pounds the section and the entire middle ring of the wheel starts spinning. It then descends into another room with stars all across the wall. When it hits the bottom, it joins another middle and outer ring.
Luigi: This is a definite-a discovery!
Mario: Hey, the sounds are coming from-a the center!
???: BLEAH!!!
Out of nowhere, a giant Boo shows up. He has a crown and a huge tongue dripping down.
Luigi: King Boo?
King Boo: I can't believe this casino has cheated me and gotten all my money! I'm haunting it for revenge, plus Bowser wanted me to!
Luigi: It's times like these I wish I had a Poltergust 3000.
King Boo: You! You were the one who trapped me in that painting! In fact, if I hadn't been released by my fellow Boos, I'd still be there! And it's all your fault!
Mario: Not-a you!
King Boo: I still remember trapping you in the painting. You were a fine addition to my new Hero Art Gallery.
Mario: Wait a minute. Your gallery is called HAG?
King Boo: Yes! It describes a word of fear!
Luigi: Witches aren't all that-a scary. They are really the only-a monsters who are-a hags.
King Boo: Well I like the word HAG!
Mario: Go away!
King Boo: Say, let's gamble! Hehehe!
And so, the battle begins. Some slots appear in front of King Boo and the rings start spinning in opposite directions.
Luigi: Mario! What do we do?
FLUDD2: Try pounding the purple sections.
Luigi pounds the purple section of the middle ring. It stops spinning. Mario does the same on the outer ring.
King Boo: We don't have all day!
King Boo shoots out a Boo, which looks like it's drunk.
Luigi: They look different.
King Boo: It's all the time in the picture frame, Luigi!
Luigi: Oh...
The Boo turns mostly invisible, but a blur is still visible.
FLUDD: Spray the Boo.
Mario does as he's told. The Boo is now fully visible. Mario bops it on the head and it dies... well... goes away. Luigi sprays the slots near King Boo and they start spinning.
Mario: Come on, let's-a get rich!
Luigi: Aren't we rich already?
Mario: Good point.
The slots stop on some fruit. Some arcade victory music plays and fruits come down.
Luigi: Wait, is a pepper a fruit?
Mario: I hate-a peppers!
Mario picks up the pepper and throws it. It hits King Boo and his tongue catches on fire.
King Boo: PEPPERS? I'M ALLERGIC!!!
Mario: Now what do we do?
FLUDD: Try something sharp.
Luigi picks up a pineapple and chunks it at the flaming tongue. King Boo spins and flashes red for a second.
Mario: We hit him!
King Boo: You fools! Feel the wrath of... spinning!
The rings start spinning again. Mario and Luigi pound the purple sections, causing them to stop. Mario sprays the slots.
King Boo: Arrrgh!
It stops on three question marks. Some arcade failure music plays.
Mario: Uh oh.
King Boo spits out a bunch of enemies. Luckily, Mario and Luigi have seen all of them before and can easily dodge and defeat them.
King Boo: Arrrggh!!!
King Boo makes the slots and the rings spin, you know. Mario and Luigi pound the purple section of the inner and outter rings. Mario sprays King Boo and the slots start up. Fruits again. King Boo shoots a bunch of fruit out, same as before. Mario throws a pepper at the ghost, and Luigi finishes the attack with a pineapple.
King: Graaahhh! This is so annoying!!!
The rings spin.... yeah. Mario sprays the slots with the last of his water.
Mario: Uh oh!
Luckily, the slots don't match up and a bunch of bubble shoot out. Mario and Luigi bop some and take water. As soon as the bubbles hit the wall, however, they multiply. Mario and Luigi get roughed up a bit, but they use the coins in their pockets to recover.
Mario: I'm-a glad you got-a lucky, Luigi!
Luigi: Me too!
Next.... *pound* *pound* *pound* *spray* *slot turning sound* This time, it stops on the fruit again.
Luigi: Hurry! This is our-a chance!
Mario and Luigi use their strategy with the pepper and the pineapple to finish off King Boo once and for all. As soon as the pineapple hits, King Boo starts to blow up.
King Boo: Come my Boos! We must flee!
And so, King Boo and most of the Boos flee back to the ghost house they came from, and the king is replaced by another Shine Sprite. Mario makes a reach for it.
Luigi: Mario, wait!
Mario: What?
Luigi: Can I have this one? He's an old-a foe of mine.
Mario: Haha. Sure, Luigi.
Luigi: Thanks!
Luigi grabs the Shine Sprite and gets to do the Shine Dance again.
Luigi: Come on! Let's-a get our money!
When the roulette wheel goes back up, they see Shadow Mario making a run for the exit with their bag of coins.
Luigi: Noo!!!
Shadow Mario: Boy is King Dad gonna be proud!
Luigi tries to give chase, but they are teleported back to Delfino Plaza.
Luigi: *sigh* Oh well. Easy come, easy
go.