King Boo: Okay, you guys failed at getting that Crystal Heart!
King Boo is seen scolding Booario and Booigi, who have been burnt to a crisp after being hit by Mallow's shocker attack.
Booario: We're deeply sorry, King Boo.
Booigi: We weren't expecting them to be THAT powerful.
King Boo: *sigh*
King Boo turns to Princess Boo.
King Boo: Would you please heal these guys?
Princess Boo: Of course.
Princess Boo raises her stubs and they let off a glow of light. Two beams come from the stubs and hit the Boo Bros. They begin to heal and feel a lot better. Princess Boo finishes healing them and the Boo Bros. feel great.
Booario: When was she able to use that?
King Boo: Her powers are finally kicking in. The best part is, when she discovers a new power, she already knows how to use it. Anyway, let’s find the next location.
King Boo heads to the Crystal Ball and starts looking. Then an image appears. It looks like a big windmill with tan- colored Boos around it.
King Boo: Gusty Gulch!
Then, another image appears- a giant Clubba with a Duplighost.
King Boo: ... Them!
Booario: What is it, sir?
King Boo: Tubba Blubba and Doopliss! I haven't seen them since the Star Portal Fiasco!
Booigi: So, they have the Crystal Heart?
King Boo: Unfortunately. They locked it up in the Gusty Gulch Windmill. So, I need you guys to retrieve it.
Boo Bros: WHAT?! Oh come on!
King Boo: Yeah, so go!
Booario: You mean there is still no sign of Booster?
King Boo: Hehehehehe. Oh, he turned up. But I sent him on a different mission.
Booigi: Which would be?
King Boo: Since Bowser is out with the Mario Bros. searching for the Crystal Hearts, that leaves his keep defenseless. So I sent a couple troops to Booster’s location, and they set out for Bowser's Keep.
Booario: *sigh* All right. We'll go.
Booigi: Under one condition.
King Boo makes a confused expression.
Booigi: You have Prof. Boo create something to give us an advantage!
King Boo: Eh, why not? Just go to his lab and find something.
Booario and Booigi rush to Prof. Boo's lab to find something that will give them an advantage.
Bowser: We have to get to the Keep!
Mario: But what about the Crystal Heart?
Kamek: Where is the next one?
Luigi: Gusty Gulch.
Kamek: We do have to fly by Boo Mansion in Forever Forest... We'll drop you off there, try to save the Keep, and come back and join you later.
Mallow: That works.
Kamek: To Forever Forest!
The Koopa Cruiser flies off and heads for Forever Forest. They eventually make it and drop Mario, Luigi, Mallow, and Geno off at Boo Mansion. The Cruiser flies away and heads for Bowser's Keep. Mario and Co. head for the mansion so they can explain to Bow why they need to head for Gusty Gulch.
Booster: All right men, I know there are still Koopa Brats around here! Hunt them down, and throw them in the dungeon!
Boo Soilders: SIR, YES SIR!
They leave and search the Keep for the Koopalings. Two Boos pass a trash can. The lid lifts up, and Lemmy slowly gets out. He starts walking quietly down a hallway.
Lemmy: Oh man, I have to find the others. I just hope that that jester Boo didn't capture all of my siblings.
Lemmy passes a closet. The door opens and he is pulled in. He looks for the light switch and turns it on. When the light turns on, he sees Bowser Jr, Ludwig, and Larry. Larry quickly turns the lights off.
Lemmy: What was that for? I can't see a thing.
Larry: We can't let them know we're in here.
Lemmy: Oh, well, thanks for bringing in here before I was captured.
Ludwig: So, did you get a hold of Dad?
Lemmy: I tried, but Kamek answered, so I told him what was going on, until that jester Boo found me.
Jr: Do you think he is part of King Boo's army?
Ludwig: Well, I was reading a book before he came to the Keep. I was reading about a fierce ruler named Booshido who had ten lackeys he called senshi, which is Japanese for warrior. They were a Tanoomba, Duplighost, Shy Guy, Yoshi, Dry Bones, Lakitu, Blooper, Shroob, X-Naut, and Boo. They were all ranked from one to ten, one being the best senshi.
He reaches into his shell, grabning a flashlight, pen, and paper. He writes the order down and shows it to the others by shining the flashlight on the paper. This is what was written down:
1. Boo- Booster
2. Shroob- Shroobiorra
3. Yoshi- Spikeshi
4. Shy Guy- Senshi Guy
5. Duplighost- Samurghost
6. Dry Bones- Bonz
7. Blooper- Bloopshi
8. X-Naut- Senshi X
9. Lakitu- Senshitu
10. Tanoomba- Senshioomba
Larry: What is the point of showing us their names and ranks?
Ludwig: I'm trying to point out that the Boo that used to work for Booshido is the Boo that is attacking us!
Jr: We have to find out more on this guy. We have to head for your lab.
Lemmy opens the door, looks both ways, and motions the others that it's safe. They slowly walk out of the closet and try to avoid Boos. Unfortunately, right outside of Ludwig's room, they run into two Boos. Lemmy and Jr. fire ice and paint at them. Larry and Ludwig fireball them. The Boos don't see it coming and are knocked out. The remaining Koopalings take the Boos to a nearby closet and hide them there. They head into Ludwig's room and find the lab. Ludwig grabs a book and turns it to a page that has a picture of a Boo that looks exactly like Booster.
Lemmy: That's him!
Ludwig: Hold on, let me read before we jump to conclusions. Ahem. Booster, one of Booshido's senshi. Booster was the most powerful senshi of Booshido's lackeys. He was able to perform both powerful martial arts and magic with his jester stick. Looking like a jester, Booster loved to clown around during battles. But even through he would be clowning, he still performed powerful magic. Later in time, when he learned the use of machines, Booster had someone build him a robot. When the robot was finished, it looked like a jack in the box, only the thing that popped out was a Boo that looked like Booster himself. Booster named this machine Boo in a Box. He caused major havoc with it until a wizard named Merlan came along and stopped Booster along with Booshido and the others by using his own creation, the Crystal Stars. He used their combined power and froze them in time. To this day, none of them are living.
Ludwig: All right. We'll use the Internet and look him up.
Ludwig heads over to the computer and types in Booster. A screen pops up and shows the years he has lived.
Ludwig: Okay, here it is. 1945 to now... NOW?!
Lemmy: Check his status.
Ludwig scrolls down and finds it.
Ludwig: King Boo's Army.
Larry: ... Crud.
Then the door to the lab begins getting pounded on. From the other side, they hear Booster giving orders to try harder. Larry, Lemmy, and Ludwig begin to shiver. Bowser Jr. looks around the lab and notices a robot with hammers for hands, metal tubes for arms, booster rockets for legs, a round, green body with Bill Blaster, a white head, yellow glowing eyes and smile, and a short, silver pipe on the head.
NOTE: THIS NEXT SCENE WILL CONTAIN A BOSS FROM AN UPCOMING GAME. IF YOU WANT TO READ ON AND FIND OUT THE BOSS, KEEP READING. IF YOU WANT TO BE SURPRISED WHEN THE GAME COMES OUT, DON'T READ AND SKIP TO A DIFFERENT PART OF THE STORY ON THIS PAGE.
Jr: Ludwig, is that robot ready yet?
Ludwig looks at what Jr. is looking at.
Jr: How would you like to see if it works?
Ludwig gets the idea, shows Jr. the controls, and starts it up. From the other side of the door, Booster laughs evilly.
Booster: Hehehehehe. Once we capture those remaining brats, I'll give King Boo the call and we can have two bases!
The lab door begins to show dents in it from the other side. Booster questions what is going on. Then the door falls on the Boos who have been trying to break it down. Booster looks at where the door was and sees the robot I described earlier. Then Ludwig, Lemmy, and Larry come from behind it.
Ludwig: Hello Booster, we just wanted to introduce you to our little friend. We would like you to meet the all-powerful... MIGHTY MALLETOID!
Booster: Why you little...
Then a Boo comes in with a panicked look on his face.
Boo: Sir, Bowser's Koopa Cruiser is heading this way! And they are going to fire their weapons!
Booster: I'll take care of them…
He turns to the Koopalings.
Booster: -after I take care of these guys. For now, you guys take care of them.
The Boo rushes off. Then Booster summons his jester stick and opens it. He opens the top and presses a button. Then, from above the ceiling, a box with a Boo making a different face on each side falls down. It then starts to jiggle. The top opens and a Boo that looks like Booster, only with claws for hands and springs for arms, appears. Two slots at the sides open and out come ray guns on each side. Booster floats up to the top and opens the hatch and begins to control it.
Booster: You wanna fight like that? Then it shall be! Meet Boo in a Box 2.0!
Lemmy: Dude, you just killed the mood.
Larry: Yeah, try to come up with a more threatening name.
Booster: SHUT UP! I LIKE the name. NOW PERISH!
BOSS BATTLE: Boo in a Box 2.0
Mighty Malletoid: Let's see how you like THIS!
Mighty Malletoid swings his hammer arm toward Boo in a Box's base. He makes contact and sends Boo in a Box back a little. Boo in a Box counterattacks with a rapid firing of blasts from the ray guns. Mighty Malletoid blocks the hits by protecting himself with its hammer hands. He then opens up his chest and fires a Banzai Bill at high speeds. It hits, but Boo in the Box still has tons of energy left. Booster punches in a code and Boo in the Box starts to grow to a bigger size than Mighty Malletoid and gets sharper teeth and claws, and a ray gun appears out of the head of the Boo. Booster laughs and presses a button that causes all the weapons to fire. The two ray guns and the one on the head start firing rapidly. From inside, Bowser Jr. pushes a couple buttons and Mighty Malletoid tucks in his head and arms, making his body a super shield. The blasts bounce off of Mighty Malletoid and head straight back to Boo in a Box. The rays do a ton of damage to him. Might Malletoid is brought back out, and he charges toward Boo in the Box and starts hammering the robot constantly. Soon Mighty Malletoid has left so many dents that Boo in the Box explodes and Booster is sent into the ceiling. He hits it and falls back down. Ludwig, Lemmy, and Larry approach Booster. He then begins to laugh.
Booster: Hehehehe. Hahahahahahahaha. Bwahahahahahahahahaha!
Lemmy: What's so funny?
Booster: I just think it's funny that you beat me so easily. To tell you the truth... I'm better as a solid fighter.
Ludwig: What do you mean?
Booster: I mean that I know you have been studying me. I knew you were hiding in a closet, so I told the Boos I would patrol the area. I put those two Boos in front of your room just to see your power. It's not that bad, but compared to mine, it's weak. I wanted to see what you would throw out when you found out we were banging on the door. I was impressed by the robot. But I wasn't even trying. If I had been, you would've been dead! And it is true, I was part of Booshido's senshi, and I was the best! And I'm about to show you why I was, and still would be, the best!
Booster then begins to glow. He then grows. As he is growing, his body changes. He becomes long like a snake, and his arms get longer and he obtains three-fingered, clawed hands, and two horns on his head that look like the Pokemon Rayquaza's. He also gets the face of Rayquaza. He still has his red eyes, but his tongue is now serpentine. He also has wings. His voice becomes deeper as well.
Booster: BWAHAHAHAHAHAHAHAHA! This is the reason I'm the best. It's because of my release form! This is it! Your lives end here! THE UNDERWHERE AWAITS YOU!
Mario: Take this!
Mario whacks Booario with his hammer, sending him into the wall of Tubba Blubba's Castle…
After Mario and Co. were dropped off, they told Bow what was happening and she let them go to Gusty Gulch. Mario and Co. headed for Tubba Blubba's Castle, where Tubba and Doopliss happily greeted them. Mario told them what was going on and Tubba happily gave them the key. But they were then ambushed by Booario and Booigi, who they are now battling.
Booigi: Go get 'em, Boos!
Booigi commands the army of Boos they brought to attack. There are too many for Luigi and the others to fend off, so Tubba jumps in and mega-punches half of them. Doopliss transforms into a Bomb Boo and explodes on the other half of the Boos.
Booigi: Take this!
Booigi fires a stream of green fire. Geno jumps in and puts up a shield. Meanwhile, Mario and Booario are duking it out.
Booario: Not bad. You're pretty talented with a hammer…
Booario reaches into his mouth and pulls out the mechanical hammer he got from Prof. Boo.
Booario: But I'm better!
Booario starts spinning and heads toward Mario. Mario jumps out of the way, but Booario has perfect control and moves toward the spot Mario landed on and makes contact. Mario is sent into the wall. Booario stops spinning and laughs.
Booario: How do you like that? Prof. Boo gave it to me.
Booigi: And I got THIS!
Booigi reaches into his mouth as well and pulls out a headband.
Booigi: Luigi, let’s see if you remember when we hypnotized Booser and gave him this ability!
Booigi puts the headband on and begins to transform. He transforms into Luigi!
Luigi: But... last time, I battled a zombified Luigi.
Booigi: Yes, but this band gives me the ability to transform into a human form of you! And, I get free power-ups!
Booigi reaches into his pocket and grabs a Fire Flower. He turns into Fire Booigi and starts shooting fireballs. Luigi and the others started doing a series of jumps. Mallow then summons a rain cloud. It starts pouring down rain on Booigi. Booigi loses his fire power and is drenched. Mallow then performs Shocker. Booigi is badly electrocuted. Then Geno uses his Star Run, and Luigi finishes him with a swing from his hammer.
Mario and Booario are seen smacking each other’s hammers. Mario then jumps and hammers Booario's head. Booario gets angry. He then smacks his hammer on the ground and shockwaves start moving toward Mario. Mario leaps into the air and goes for another smack on Booario's head. But Booario acts fast and opens one end of the hammer and bullets are sent out. Mario is wide open. Then Doopliss leaps in and transforms into a shield and deflects the bullets. He then transforms into a Koopa shell, and Mario smacks him into Booario, who is launched into the wall and loses his hammer. It lands in front of Tubba, who destroys it with one stomp. Booario and Booigi, who transformed back to normal, are defeated.
Mario: If we ever see you again, you will regret it!
Booario shivers and grabs Booigi.
Booario: We'll be back!
Booario flies through the wall while carrying Booigi and heads back to the Mushboo Kingdom. Mario sighs and turns to Tubba and Doopliss.
Mario: Thanks for the help, guys.
Tubba Blubba: No problem.
Doopliss: Yeah. It's what friends do. Now, go and get that Crystal Heart so you can stop King Boo.
Mario and Co. head for the windmill to get the heart. They use the key, head deep into the windmill, and find the Crystal Heart. They take the Heart with pride and head back to Starborn Valley by using the pipe back at Boo Mansion that leads to the sewers.
Boo: FIRE THE BULLET BILLS!
From on top of the Keep, some Boos are seen handling the Keep's cannons and are firing Bullet Bills at the Koopa Cruiser. From atop the cruiser, we see Bill Blasters handled by Koopatrols, Kamek, and Bowser.
Koopatrols fire the cannons, Bowser breathes fireballs, and Kamek fires spells. Everything collides and causes an explosion. But some bullets and fireballs made it through. The attacks hit the top of the castle where the Boos are, causing a lot of damage.
Boo: SWITCH TO BANZAI BILLS!
The cannons get swapped for Banzai Cannons. They start firing Banzai Bills rapidly.
Bowser: Kamek, up the power of my fireballs and the Bullet Bills.
Kamek uses a spell that powers up Bowser as well as the power and speed of the Bullet Bills. Bowser and the Koopatrols shoot fireballs and Bullet Bills at high speeds and break through the Banzai Bills, blasting the Boos off the castle.
The Boos start flying past the Cruiser and head back to the Mushboo Kingdom.
Kamek: Well, the castle is safe. We just need to make sure the Koopalings are okay and...
Before Kamek can finish, an explosion is seen from the east side of the castle.
Bowser: Head over to where the explosion occurred.
The Cruiser flies over and Bowser jumps down a hole the explosion made. When he lands, he sees Larry, Lemmy, Ludwig, and Jr. being attacked by a dragon. Jr. starts flinging paint toward the dragon's mouth to stop it from firing beams, but the dragon quickly dodges everything and whacks Jr. into a wall with his tail. Larry fires a blast from his scepter, Lemmy blasts the dragon with his Freeze Gun, and Ludwig shoots fireballs. The dragon swiftly dodges everything. Then he forms two energy balls and fire them at Larry, Lemmy, and Ludwig. They are all hit and sent into the wall. Bowser then charges toward the dragon and shoots fire in the back of his head. The dragon turns, sees Bowser, and puts on a smug grin.
Dragon: Hehehehehehe. Bowser... we meet again!
Bowser: What are you talking about?
Dragon: Maybe this will help you remember.
The dragon lets off light and begins to shrink and get smaller arms, losing its horns and becoming round. He also gains a jester hat and stick. He has become...
Booster: Remember now?
Bowser: YOU! How did you survive?!
Booster: Hehehehehe. When you sent me flying, I landed in the coldest village possible. Then a Shy Guy wearing black robes took me in. When I woke up, I was confronted by a Boo with a black-hooded robe over him. He told me that the Shy Guy found me outside and brought me in for warmth. He invited me to stay awhile, but I told him I had a mission to complete. I rushed outside and teleported to a random spot I knew, and I ended up at your Keep! So I called King Boo and had him send some troops over, thus giving me the opportunity to...
Booster turns around and sees Jr. coming right at him with his paintbrush. Booster then stops him with his jester stick, knocks him out, and fires a blast that sends him through the roof.
Bowser: NOOOOOOOOOOOOOOOOOOO! NOT MY SON!
Booster: Bwhahahahahahahahaha! Now that that's done...
While Bowser has his back turned, Booster charges up a blast from his stick and fires it at Bowser, knocking him out.
Booster: Now that you're knocked out, I can call King Boo.
Booster pushes a button on his stick and a small screen appears. On it, King Boo appears.
King Boo: Ah, Booster, how did the attack go?
Booster: How about you send some troops over to protect the Keep.
King Boo: You mean... the Keep is yours?
King Boo: Very good. I shall have troops over soon.
The screen turns off and Booster laughs.
Booster: Hehehehehehe. I have plans for YOU, Bowser!