A/N: Even though my first story isn't getting a lot of reviews, I have received over 250 views. But I like to give a special shoutout to Steel Magic. If you are reading this, thanks for reviewing each chapter you read. The feedback helps out a lot for me and I'm glad you love the story so far! Unfortunately, this chapter, plus another one coming up, will be fillers before we get to the story conflict. Nonetheless, thanks again for the support!

*NOTE: I changed the chapter title because the old one felt stupid to me.

Disclaimer: I don't own rights or the characters to Mario and Sonic as they belong to Nintendo and Sega, respectively.

Chapter 4: The Professor Is In

Princess Peach and the rest of her group joined Toadsworth and her servants as they decorated the castle for Luigi's party. While they continue the contribution, the others decided to spend time in different regions of Mario's world. Yoshi invited Silver and Knuckles to Yoshi's Island to say hello to the other dinosaur inhabitants. The Kongs took the Chaotix to the Kongo Jungle and explored the vast forest searching for bananas and joining the members of the monkey bunch. They all planned to be back at the castle at around eight, which is when they'll start the night festivities.

Then there's Mario, who left the others claiming that he had something important to do. Unknowingly to them, Mario forgot to get a gift for his brother. He had to search through every store in Toad Town to think of the perfect present. To his dismay, the red plumber was clueless and couldn't decide on what to buy.

Location: Boo Woods

Meanwhile, the trio of Luigi, Tails, and Sonic were making their way (downtown) to meet up with Professor E. Gadd in his lab, located in the deep part of Boo Woods. (1) It was a long walk for the three heroes, but they managed to make it there. And thanks to Sonic and Tails, Luigi felt more relaxed that he had company while strolling through the creepy forest.

Behind the professor's indoor laboratory was Luigi's personal mansion, a tall three-story building with white walls, green windows, and a large 'L' symbol placed on the top-center. (2) But since Luigi is usually the only resident who lives there, he doesn't spend that much time at his personal mansion as often as the shared house he and Mario live in. Nevertheless, he always kept the key to the large building.

As they approached the lab, the man in green knocked on the door three times, waiting for a response. "Hello? Professor Gadd?"

After a few seconds passed, a speaker found above the door emitted a familiar voice. "Aah, Luigi! You have arrived! And with some friends, too. Come on in!" They made their way inside and headed towards E. Gadd's bunker, filled with his most prized possessions and inventions. Eventually, the three saw the short, old man with spiral glasses and a white lab coat.

"Good morning, Professor E. Gadd!" Luigi called.

"Hohoho, Luigi! Good to see you, my lad! I reckon you got the message from the princess, yes?"

"I sure did!" Just then, a bark came from behind E. Gadd, which turned out to Luigi's Polterpup came running enthusiastically towards him, with a bell dangling from his trademark red collar. The ghostly dog jumped up to his owner and started licking his face, causing Luigi to laugh. "Hahaha, hello Colombo! (3) It's good to see you, too." He patted his pet's head and gave him a belly rub before getting back up on his feet.

"Professor, you remember Sonic and Tails, right?"

"Oh, how can forget about these two nice folks? Great to meet again!" The professor shook both of their hands.

"Well, it's great to see you again, Professor," Sonic smiled.

"So how's it going? Have you been working on any inventions?" The curious fox asked. Knowing that E. Gadd is a fanatic with inventing and machines, Tails couldn't help but ask. He shared a strong relationship with the old chap.

"Actually, I have been creating something new and modified to one of the few gadgets I gave Luigi back then. In fact, it's the present I wanted to give you, sonny." The professor turned and walked over to his garage. After fumbling with his pile of inventions, he grabbed a wrapped box with a tag that said 'LUIGI' in big, green letters. "Happy birthday, Luigi! I hope you like it."

Luigi thanked E. Gadd and began to unwrap the gift. After taking off the top, he was astonished. Inside laid a familiar, large portable device. It had a green, sleek texture with a white circle and a large green L in the center. "Oh, wow! Another Dual Scream!"

"Aah, but this one is more technologically improved. Introducing the 3D Dual Scream! (4) This device is just like your old DS communicator, but with an improved battery life, a larger contact list, cameras, and it even provides classic portable gaming! But the big difference is that you can use the 3D slider to enhance your views when you take pictures or play games. Either way, this should be an enhancement to the original, bulky Dual Scream since the 3DS is lighter, despite its big size!"

"That's pretty impressive! Thank you so much, E. Gadd!" Luigi acclaimed.

"But wait! There's more! Since I know you're having a party at the castle and it won't start until tonight, I thought I would give you these!"

The professor signaled the Polterpup who barked in response. He went over to a table and grabbed a yellow envelope. Luigi took the package from the dog's mouth; inside was a large amount of guest passes and ballgame tickets! The passes were for the world-famous Mushroom Park, an amusement area full of high thrill rides, delicious food, fun minigames, and stunning aquatic shows featuring well-trained Dolphins, Cheep Cheeps, and Bloopers. The tickets allowed access to the Fireball Stadium, a large baseball stadium where thousands of spectators would cheer for the home team: the Flamin' Shrooms. Both landmarks were located outside the heart of Mushroom City.

"Whoa, this is incredible! I haven't been to Mushroom Park or Fireball Stadium in a long time!"

"Fireball Stadium? Mushroom Park?" Sonic raised an eyebrow. E. Gadd explained the two attractions to him and Tails, since they don't know much about the kingdom's famous landmarks. After discussing about it, the two friends got excited immediately.

"Wow, that's sounds like a lot of fun!" shouted Tails. "We should tell the others about this!"

"I'm sure the others would like to join you for a day of excitement and baseball. Speaking of which, where is that brother of yours, Luigi? Didn't he come with you?" Professor E. Gadd turned to Luigi, who gave him a somewhat sad look.

"No, professor. He said he had something important to do in town. It was strange, like he was forgetting something."

"It did seem peculiar of Mario just to leave like that, as well. I saw the look on his face and he seemed panicked and embarrassed about it," Sonic added.

The professor shook his head, but still sported a grin. "Oh well. I'm sure Mario will be done with his duties. But don't worry about that. Run along and have fun at the park and ballgame. It is a special day for you all. Anyways, I'll continue looking after Polterpup. He's been helping me fetch some equipment for my new projects or trying to learn tricks with that gold bone of his."

Colombo whimpered. He was sad to only see his owner for a little while. Unfortunately, he can't go with Luigi and his friends because the stadium and amusement park do not allow pets inside, unless they're service animals. Luigi noticed the depressed look on his face and rubbed its head. "Don't worry, il mio cane. (5) When we get back, I'll take you the party we're going to be throwing at the castle!" That brightened up the pup's mood as he began panting and wagging its tail to show his excitement. That also made Luigi put on a big smile, too.

"Well, thanks again for the gifts, E. Gadd. I'm sure we'll have a great time!"

"Come on, guys! We better tell the others right now. Maybe you can use that 3DS to contact them," Sonic replied.

"Bye, Professor Gadd! Bye, Colombo! Hope to see you soon!" Tails waved his hand to the old man as the three began to leave the lab.

The professor also shared his goodbye and waved back. The Polterpup barked back at their departure. Once the heroes were gone, the two went back to work, cleaning out the garage and drawing out blueprints for another invention.

Within a matter of minutes, Luigi fiddled with his new 3DS to add the contacts to his friends, both Mario and Sonic's. Like the original DS and the Game Boy Horror, there was a video chat communicator to contact his friends. He called the others telling them about the gifts he received from E. Gadd and invited them to join them at Mushroom City where they would be to the heart's content to enjoy the ballgame and spend time at the amusement park before they head back to Peach's Castle in time for the party.

Everyone managed to receive Luigi's calls and they were ecstatic to spend the afternoon at an amusement park AND at a baseball game. Even the Princess was excited about the event that she decided the others to take a well-deserved break to have some fun. Toadsworth assured her that he and the Toad staff will finish the rest of the party setup, but also warned her to be careful, being the overprotective Toad he is.

Location: Mushroom City

It was 11:45 by the time Luigi, Sonic, and Tails found their friends, including Mario who was finally finished with his errands. The red plumber apologized for not being with him during his visit at E. Gadd's place. Luigi accepted his apology and the entire gang got ready to depart to the ballgame which would start at noon. The tickets the professor gave to Luigi were the best seats in the house: sitting behind home plate watching all the action between the offense and defense.

In front of a sold-out crowd full of outgoing Toads, Piantas, Nokis, Shy Guys, Koopas, and Goombas, the Flamin' Shrooms were hosting their rival, the Koopa Shelltops, one of the toughest opponents in the league known for their dangerous lineup. Both teams showed off their skills on the diamond with players showing off excellent defense to rally up the crowd. As for the offense, the Shrooms managed to score some runs against the Koopas thanks to Rex T., their strongest player, hammering a two-run bomb to left field, exciting the crowd for taking the lead, especially the Mario and Sonic parties.

Throughout the game, Sonic would always taunt the road team for being too slow to catch a baserunner stealing or if their throw to first base was too late. He started to get too cocky that security threatened to escort the blue hedgehog out of the sporting event if he continued.

Knuckles would get frustrated when the Shrooms' defense made a critical error on the field; one occurrence had a Toad misplay an easy pop fly in center, leading to two runs for the Shelltops. This caused Knuckles to accidentally hit Tails in the back of his head due to his annoyance. The fox responded back with a loud slap to the echidna's face.

Cream and Cheese were able to get an autographed ball from one of the Shrooms' players. Yoshi, DK, and Diddy either walk around the ballpark looking at all of the food stops in the stadium. In between innings, the Chaotix, Rouge, Toad, and Toadette went to see the fun activities and games set up outside the park. The rest of the group continued watching the ballgame.

Entering the bottom of ninth inning, the Shrooms were down by 4-2. But after a chain of hits and misplays by the Koopas, Rex T. was up with the bases loaded and one out. The sold-out audience were all on their feet, chanting the batter's name in hopes of a comeback win. Mario, Sonic, Luigi, and Tails were the most enthusiastic with the adrenaline rush. With a determined grin on the batter's face, he stepped into the box, ready to face the pitcher. A tan-skinned, buff Koopa was waiting for the signs from his catcher in an attempt to retire the fearsome slugger. The closer winded up and threw a nasty slider to Rex T.

Swinging on the first pitch, the strong Toad crushed the ball to straightaway center. Soon the audience started cheering as the projectile continued to sail high in the sky. The center fielder was running towards the wall and leaped up to reach over, but the ball was out of reach as it landed for a walk-off, game-winning grand slam!

Fireball Stadium was ecstatic, overjoyed, and amazed at the Shrooms' come-from-behind victory over the Shelltops by a final score of 6-4. The gang was jumping for joy, exchanging high fives with each other, and shouted "Rex T. for MVP!" as they waited for the slugger to be mobbed by his teammates over home plate. By the time the game ended, it was almost 3 p.m. and the group headed out to Mushroom Park as they continued having fun on Luigi's big day.

END OF CHAPTER

Just a placeholder chapter to show the events between Sonic's arrival and the upcoming party. I decided to add a baseball game to make this longer (since baseball is played in the summer). I tried my best to describe some of the general actions of the event.

Post-Chapter Notes:

(1): That's a lyric reference to 'A Thousand Miles' by Vanessa Carlton. I don't own rights to the song whatsoever.

(2): Believe it or not, but I have NEVER played the original Luigi's Mansion, but I have watched Let's Plays of the game and did some research on Super Mario Wiki. The one I described is the 'Rank A' Mansion, which is found as an Easter egg in Luigi Circuit from Mario Kart: Double Dash. However, in Dark Moon, Luigi resides in the 'Rank D' house.

(3): I looked up a website for Italian dog names and their meanings so I can give Luigi's dog a name in case 'Polterpup' was too redundant. I chose the name 'Colombo', which was described for a dog that 'likes to seek and explore'.

There are probably better names out there and this one may not be too fitting, but I thought it suited the dog who's known for its mischievous behavior and adventures in Luigi's Dark Moon quest.

(4): Typically, it's a new Nintendo 3DS XL, but with a special design fittingly for the green plumber.

(5): 'Il mio cane' is Italian for 'My dog' (courtesy of Google Translate). I wanted Luigi to use show off his own foreign background as an Italian plumber.