Act IV, Sc. 3

At 11:45, Luigi used the key of spades to get to the final room. Inside it he saw a large Boo wearing a giant crown. Luigi knew who he was in an instant: King Boo.
"Aahh, I could just stare at my two finest paintings for hours," King Boo sighed happily. "It's true what they say about fine art… it takes utterly refined sensibilities to truly appreciate it. The way you plead for help… I find it so… satisfying."
Luigi hardly dared to move an inch, but Pikachu got more and more cross.
"Perhaps that is merely because I remember how much trouble you've caused me in the past," continued le roi phantôme. "Seriously, though, who would believe that mansions get given away in contests?! Talk about stupid! What do they feed you on anyway… gullible soup?"
"Stupid indeed," thought Luigi to himself.
"He is right," thought Pikachu. "They came all this way to become paintings."
"Now we'll become paintings," thought Drifblim nervously.
"Not if Luigi defeats him," thought Decidueye.
"Courage triumphs over cowardice," thought Noctowl confidently.
"At least I'm safe inside my mind," they all thought together.
"You two came all this way just to get turned into paintings," King Boo smiled. "It's just terrific."
"NOOOOOOOOOOOOOOOOOO!!!" yelled Luigi.
"However," King Boo continued before turning around, nearly scaring the daylights out of Luigi but not making a dent in Pikachu's stature, "these two paintings look lonely. I must have a painting of Luigi and Pikachu as well! Then my gallery will truly be complete! I am not afraid of you, fools! I fear only that infernal Poltergust 6000P you carry on your back! Stupid machine!"
"Maybe so," said Pikachu, "but we refuse to let you take all of us! We won't let Princess Peach fall once again into Bowser's hands!"
"But I am a KING amongst Boos," King Boo continued. "I swear it… I shall fear no mere house-cleaning device! I must say, I despise the way you vacuumed up all my friends!"
"I doubt that you will have the cowardice of your kind to face up to the Poltergust 6000P," said Decidueye boldly.
"Don't imagine that I'll flee," cried King Boo. "I'll fight you like a true Boo! Now join your friends… inside the paintings!"
In an instant, the two paintings were replaced with a large one of Bowser. Neither Luigi nor any of his four Pokémon could escape the void of being sucked into the painting.
On the roof, or what looked like the roof to Luigi, the five of them came face to face with what looked like a giant Bowser, when in fact it was a well-constructed robot controlled by King Boo. It blew fire, created an infinite void, threw spiked balls, etc. Luigi got an idea. He grabbed one of the spiked balls and knocked off Bowser's "head," from which King Boo emerged. Luigi used the Poltergust 6000P with all his might, and his team wouldn't let him down. King Boo fought hard, but not hard enough. Eventually the "head" went on backwards, and Luigi had to avoid Bowser before it reverted to its normal position.
The battle raged on for what seemed like years to Luigi, but it was only a matter of minutes. In the end, Luigi stole the crown and King Boo was dethroned. The Bowser automaton collapsed in defeat, and the quintet was transferred to the Secret Altar once more. Luigi grabbed the paintings of Mario and Ash and headed back to the lab; but first he had to warn the princesses. It was 11:55. "Only five minutes left," Luigi thought to himself.