The Floating Island (Cave Story)

Indeed they do. Speaking of Alex, he is about 3/4 through the winding, multistory path.

Which reminds me, Aya appears on the surface and looks around.

Aya: This is the Floating Island? *Sees a nearby monster.* Weird...

...

Merloco examines the area where the boulder was originally.

Merloco: Hey guys...

Yoko clears her throat.

Merloco: Don't start with me, woman... Anyways, it appears there are two sets of foot prints here. One looks like Alex's, so that's good news, but the other one... looks kind of familiar.

Curly: Would they happen to be large and square-shaped?

...

The monster is a generic Critter, who runs away from Aya.

Merloco: Yeah, actually.

...

Aya starts walking down a path towards Jenka's house.

Curly: Balrog! So this is where Misery sent him...
Curly looks at the footprints.
Curly: There doesn't seem to be any signs of a struggle, though... so why would he be...
Quote taps Curly on the shoulder and points to the boulder.

Merloco looks at the boulder and then looks at the spot where the boulder was.

Merloco: You think he helped him?

Curly: Yeah. We'd better hurry and catch Alex before he does something stupid.
Curly and Quote run through the hole in the wall, the White Platoon following.

...

Random skeleton crocodiles watch Aya.

Merloco, Julius, and Yoko follow the others.

...

Aya reaches Jenka's house and knocks on the door.

Meanwhile, Alex gets to a chamber at the end of the path and enters it... but the door slams shut behind him.
Alex: HEY!

...

You should know what Jenka says by now. If you forgot...
Jenka: Are you a monster?

Aya: No, I'm a human.

Jenka opens the door.

...

The White Platoon continues down the path, noting the bug corpses.

...

The Core floats up from the floor of the room Alex is in.

Aya walks in.

...

Merloco: This looks like Alex's work. We have to hurry!

The puppies in Jenka's house stare at Aya.
Jenka: Can I help you, dearie?

...

The White Platoon does so.

...

The Core shoots lasers at Alex, who leaps onto some platforms in the air to dodge.

Aya: I was wondering if a black and orange Koopa and some other people passed here.

Jenka: Yes, they did. They were looking for an entrance into an evil old temple and got my puppies back.

Aya: Could you tell me where this temple is!?

Jenka: Just go up from here, missie. It's the huge, evil-looking structure. You can't miss it.

...

The White Platoon gets to the door and sees Alex and The Core on the other end (there's an invincible glass porthole on the door).
Curly: Darn... we're too late.

Aya: Great! Thank you!

Aya runs out of the house and towards the Temple.

...

Merloco: What do you mean!? What's going on!?

The temple is large, forboding, and has ogres outside erecting large statues of Morbul. Also, the front door is locked.

...

Alex leaps onto the core and slices it repeatedly.

...

Curly: That thing he's slicing is the core of the island. It holds this place up. If he destroys it, this island will come crashing to the ground.

Aya hides behind the tree and waits.

Aya: So this is it... *looks around.* Where are they?

...

Merloco: How do we get him out!?

The ogres don't seem to notice Aya.

...

Voice behind Merloco: You don't.
The White Platoon turns around to see Misery.

...

The Core shakes Alex off into the shallow water at the base of the room, but Alex quickly leaps back up... while dodging lasers.

Merloco turns to Misery and glares at her.

Merloco: You planned this from the start, didn't you!?

Misery: Me? Plan a scheme like this? No. Why would I want to crash my home into the world?

...

Alex turns into Dark Alex and shoots lightning at the Core.

Merloco: You tell me.

Misery: I don't. Evidently, that Koopa does. Otherwise, why would he be trying to destroy the Core... trying to crash the island into the world... trying to cause the deaths of millions?

...

The lightning stuns the Core, giving Alex a chance to fly up to it and slice it repeatedly.