This is Goblin. He appears as you approach and acts as a platform, though he has retractable horns to make using him as such difficult, and will produce Mini Goblins whenever Mega Man is above him.
(It's a mouth.)
(It's a nose. --Ed.)
There are five Goblins in total, which may be overdoing it a little, but they're interesting and each is at a different respective elevation, so I'm not complaining. The serious-looking fellow on the cloud is Kaminari Goro, who moves in a circular pattern and tosses lightning bolts when he gets close. He goes down in three hits, leaving behind a cloud for you to ride on.
This leads to some harrowing platforming in which you must kill a series of Goros and take their clouds. Two things I like about this are that players can wait for the cloud to take another pass if they're not confident in moving on yet, and that the clouds have a solid platform on them which shows exactly how high the collision point is. That can cause some confusion in lesser games that just use a cloud or otherwise irregular graphics for such things. One of the clouds eventually goes behind a larger cloud in the foreground.
Once that's established, one of the clouds will go behind the foreground for a while, forcing the player to get on quickly or catch it as it emerges. It's a great segment that puts a fun twist on moving platforms. As soon as we hit solid ground (or whatever it is) again, Pipis start flying in.
The foreground clouds now become a different sort of hazard, partially obscuring the Pipis and their eggs. The end of this section looks like it continues to the right, but...
Mega Man instead drops through a hidden hole into a room with Scworms. This is a much better use of them, as the room is open enough to avoid them but complex enough to make them a hassle. It should now be obvious to the player that they have to drop again, but there are two possible places the hole could be. The left choice is correct, and drops the player into some more clouds. I love this, as the player is now primed to expect holes and is likely going to jump through this hoping to avoid one. Actually putting one there would be awful design and they didn't do that, so it's just a fun little mind game.
There are a couple Goblins next to each other here. Jumping between them is difficult since the timing on their horns depends on when they appear, though the player can always scroll them off the screen and try again. The remaining section introduces Matasaburo, who blows Mega Man backwards and takes five hits. He's not threatening on his own, but he's combined with pits, Pipis, and foreground clouds. This continues until the boss door.
This stage is just about perfect. It has a lot going on in a small area and mixes up the assets it has for multiple challenges. The stage graphics are less varied than the others, but that's understandable since the clouds actually mean something to the gameplay and half the platforms are enemies. Also, great music.