Twilight marveled at the inside of the Gummi Ship. Not only were the various gizmos and controls almost causing sensory overload since it was her first time seeing them, but she was fairly sure this thing was slightly bigger on the inside than the outside. Magic? Or a property of the Gummis, perhaps?
"I have to say, this is very impressive. I wasn't expecting it to be quite so..." Twilight made an all-encompassing wave of her hands.
"Don't worry, half of this stuff has nothing to do with flying the ship. Some of it makes food, is for transporting us to and from the various worlds, or repairs the ship when we're not traveling." Donald explained.
"Oh, so that's what that stuff does. I wondered, but something always came up." Sora said. Twilight just barely resisted the urge to face-palm. He'd been riding around in a vehicle when he didn't know what half of it did? For a month or so? There was trusting and then there was naive.
It was at that moment that a screen came to life in front of them. Two chipmunks appeared on it. While similar at first glance, the one on the left had a black nose and buck teeth which were next to each other, while the one on the right had a slightly larger red nose and his buck teeth were separated.
"Hey guys!" black nose said, waving.
"Long time no see!" red nose said, hopping in place.
"It's your favorite Gummi Ship engineers Chip..." black nose began.
"...and Dale!" red nose said.
"Looks like you guys picked up a new friend." Chip said.
"My name's Twilight. I'll be joining in on the adventure at Master Yen Sid's request." Twilight answered, briefly summoning her Keyblade before dispelling it.
"Oh, well then let us wish you..." Chip began.
"...Happy flying!" the chipmunks finished together.
A screen on the dashboard lit up, showing two worlds and a shining path between them. One world was Twilight Town (haha, very funny universe) which they had just come from as Yen Sid's Tower was currently tied to that world, albeit loosely. The other looked to be a castle under construction with a town sheltered underneath it.
"Only one?" Sora asked, half complaining.
"That's no good." Donald agreed.
"Hm, well Master Yen Sid said that the Keyblade would guide us right? If we take care of business on this world, we should be able to reach more." Twilight hypothesized.
"I bet you're right! Besides, I think this is a world we know." Goofy said.
They flew the Gummi Ship towards the world, and disembarked.
They found themselves on a parapet that was similar to an alleyway behind what appeared to be a marketplace. The 'alley' was overlooking an enormous castle that was under something between construction and repair.
"Gawrsh, it looks kind of different now, but-" Goofy cut off.
"It's definitely Hollow Bastion. " Sora said. He brightened noticeably. "Hey, Leon and the others must've managed to put things back together if there's people here."
"I hope they're doing okay." Donald added his two cents.
Twilight turned to see a pair of Soldier Heartless on top of one of the shops. The Soldiers seemed to consider them for a moment, before vanishing in dark portals, evidently aware that attacking by themselves would be akin to suicide.
"Uh oh, looks like we'll have to some fighting!" Goofy observed worriedly. The others had turned when they noticed she had, and seen the Heartless flee.
"We can handle a couple Heartless, we might even clear them out of the town for a while." Twilight said. At that moment, a purple gem appeared, and a cartoon castle formed around it. The words 'Hollow Bastion' appeared, formed in front of the castle and with the gem as part of the 'I' in Bastion.
Sora and the others seemed to have also seen it. "Does that always happen?" she asked.
"Ahuh. Only world-travelers can see it though." Donald answered.
Deciding to ignore it, they visited the shops for some better shields and staves for Donald and Goofy. They also stocked up on Potions and a couple Ethers.
They had a short encounter with Donald's business tycoon uncle, who was apparently trying to recreate a delicious ice cream from his youth. Then they descended a staircase to find a series of narrow streets and houses, as well as a white circular pattern that appeared able to damage the Heartless if the lone Shadow that dissolved after being hit was any indication.
"Hey what's going on?" Donald asked as the circles appeared around them, but stayed outside their personal space.
"That's the town's defense mechanism. We call them Claymore." a new voice called. They looked up the nearby stone wall and saw a girl with short black hair, a sleeveless dark grey jacket over a blue and silver sleeveless shirt, a pair of brown shorts, and a pair of tan boots which had black socks peeking out over them.
"Yuffie!" Sora called in greeting.
Yuffie smiled and waved her hand, but then her expression turned into shock as she called "Look out!"
Sora summoned his Keyblade and fended off a Dusk. More appeared around them and everyone summoned their weapons and began to fight the Nobodies off. There were several morphing ones, as well as a new type that resembled a samurai. This one had a katanna and everything.
Afterward, she looked them up in her Bestiary.

'Creeper. The weakest Nobody of all. This one can change it's form to assist fighting. They have no specific weaknesses besides low mobility. They possess a snake-like base form, a spear form, a flying form, a shield form, and a sword form.
Samurai. These Nobodies have a sense of honor and prefer one-on-one combat, though that may be partially due to that being their area of expertise. As you may guess from the name, they use at least one katanna, often two. They are helpless before a superior swordsman. They are also rather slow to attack, but move quickly when they do. Their resilience is relatively poor.'

The Nobodies fell fairly easily, between the four of them, the Claymore, and Yuffie jumping into the fray halfway through. They stood no chance, despite outnumbering the combatants 3:1.
"Hey, you guys!" Yuffie said once the last Nobody had fallen. "I see you're still in top form." Yuffie said.
"Well, what'd you expect?" Sora responded. "This is Twilight by the way. She's Master Yen Sid's apprentice. Looks like you guys are doing okay." Sora said.
"Well, what did you expect?" Yuffie asked. "Nice to meet you Twilight, any friend of Sora's is a friend of ours." she added.
"Nice to meet you too." Twilight answered.
"How are the others?" Donald asked.
"Great!" Yuffie said.
"Hey Yuffie, have you seen the King and Riku?" Sora asked.
"Nope." Yuffie said before slowly walking off.
Twilight sighed as Sora slumped. "Yeah, it's never that easy, is it?"
"But I had a feeling I'd see you guys again." Yuffie said, turning back to them.
Sora struck a pose and put a serious expression on his face. "We may never meet again, but we'll never forget each other." he said, forcing his voice to be deeper than normal. Twilight couldn't fight the smirk forming on her face.
"Is that supposed to be Leon?" Yuffie asked, a grin stretched across her face. Donald and Goofy chuckled. "Everybody's working on stuff over at Merlin's house." Yuffie jerked her thumb down the path. "Come on!"
They followed Yuffie, and a few corners and several Heartless later, they entered a house a little bigger than the others. "Meet the Hollow Bastion Restoration Committee!" Yuffie said proudly.
"We missed you!" a girl with brown hair in a ponytail, a pink ribbon, a pink and white dress, and brown boots said.
"Well, ain't you in top shape!" a man with blond hair, goggles, and a workman's outfit said.
"I knew it." A man with brown hair, a scar across his face, a black leather jacket, a white shirt, a necklace with a silver lion's head, a pair of black pants, a pair of black gloves, and a pair of black boots said.
After a brief round of introductions, Sora asked. "Knew what?"
"We knew something was up when everyone suddenly remembered you guys, all at the same time." Leon answered.
"Remembered? Wait, you forgot about us?!" Sora asked.
"Thanks." Donald said sarcastically.
"It sounds like someone's been tampering with memories, nobody just forgets someone completely and then remembers for no apparent reason." Twilight said. That was definitely concerning. Maybe the Organization wasn't the only problem that cropped up while Sora and co. were out of commission.
"Hm, that might be, but we've got no way of proving it." Leon said.
"So where have you guys been all this time?" Yuffie asked.
"We were sleeping." Goofy said simply.
"Where? In cold storage?" Cid asked.
"Based on what they told me, surprisingly close." Twilight said as the others rubbed their heads sheepishly or an analogue.
"It doesn't matter, everyone's together again. This is great!" Aerith said happily.
"So um, we're trying to find Riku and the King, have you guys seen them?" Sora asked, getting a round of shaking heads in response.
"Sorry, but we'll do what we can to help." Aerith said.
"Okay, thanks." Sora said.
Cid got up and approached the quartet. "Don't go thanking us just yet." he said
"Hollow Bastion's got a problem. A [b]big[/b] problem." Leon continued.
"You mean like Nobodies? And Heartless?" Sora asked.
"That's right!" Yuffie said.
"Sounds like you could use our help." Sora said.
"We've had a few encounters already, they're part of what we're on this journey for too." Twilight said.
"Then let's cut to the chase." Leon approached them. "Sora, Donald, Goofy, and Twilight too. We were hoping you four could give us a hand with the restoration."
Sora nodded with a grin. "Like we're gonna say no." he said.
Leon smiled. "I forgot who I'm dealing with." he said.
"Hey, what's that supposed to mean?" Donald asked suspiciously.
"Just think of it as a sort of Leon compliment." Aerith said.
Leon opened the door. "Meet me at the bailey. There's something you need to see." he walked out as she got a Quest.

'Follow Leon to the Bailey. Reward: 100 Exp/Bits.'

A puff of blue smoke revealed an old man in classic blue wizard's robes. "Ah, I thought it was you, right on time, though I wasn't expecting you to have a fourth member." Merlin said, looking at Twilight in a thoroughly perplexed manner.
"It's Merlin!" Donald announced.
"Sora and the Gang agreed to help out." Yuffie told Merlin.
"Wonderful! We'll count on you." Merlin said.
"Right!" the Keyblade wielders and their companions said.
"Did you give them the cards dear?" Merlin asked.
"Oh, I almost forgot." Aerith said, before giving Sora, Donald, and Goofy three purple cards which proclaimed them honorary member of the Hollow Bastion Restoration Committee. "They're presents for you. Leon though you might like to have them." she said. "I'll make one for Twilight right away." she added.
"Membership cards!" Donald said.
"Kinda cool!" Goofy said.
"Hey thanks Leo-" Sora paused, realizing Leon wasn't there. "Oh, right! We were supposed to meet him at the bailey." Sora said.
"Ah, Sora, can I talk with you four for a second? First I'd like to be introduced to this young lady of course." Merlin said.
After they introduced each other, Merlin said. "So Master Yen Sid's finally taken on a new apprentice, and it seems he's helped you get a handle on the Darkness inside you, eh? I'm guessing he taught you the Fire and Thunder spells, but not Blizzard as cold is usually aligned with Darkness for a reason." She nodded.
"Those should do for now, but what's your status on spells Sora?" Merlin asked.
"Um, I can't remember any." Sora said sheepishly.
"You must've forgot them while we were sleeping." Goofy said.
"Very well, then. I'll teach you Blizzard. Be careful with it."
After Sora got Blizzard down, they left for the Bailey.