Ice Man starts off with a long stretch filled with Bunby Heli and awkward terrain.
As one would expect, the ground is slippery, but it is much tougher to deal with here than usual for video game ice. Jumping without pressing a direction will cause Mega Man to remain at his current speed in the air, meaning this can't be used to stop his momentum. He also slides for a very long time, and momentum persists even after running into a wall, so jumping straight up after sliding against one will cause Mega Man to move forward a bit unless the player waits for the amount of time it would take Mega Man to come to a stop on a flat surface.
Luckily, Bunby here is a simple enemy to deal with. As before, it moves toward the player when close, though in a straight line this time instead of the original's diving motion. This makes them easier to destroy, as the player only needs to start shooting somewhat near Bunby, and it will do the rest. Running and shooting randomly will carry a player through this segment just fine.
Adhering Suzy also returns. They're not too bad in this room, as dropping from the ladder can lead to a hit, and the slippery floors can cause a player to accidentally slide into one. Otherwise, their use here is similar to the first game, staying mostly out of the player's way with nothing else in the room to make them more dangerous. This would normally be too soon for a large health, but it's a reasonable choice in this case for players who had trouble getting used to the ice.
Bunby is just filler now, as the real trouble is those ice blocks. They'll melt through four different stages as the player stands on them, disappearing entirely on the fourth. This is a bad spot to introduce one, since the next platform is high enough that it becomes unreachable after the ice has melted twice, and it does so quick enough that a new player likely won't react in time. They could return to the ladder and try again if they survive the attempt, but as the ice melts and loses height, it causes Mega Man to fall a few pixels each time, and Mega Man cannot jump in a falling state. Trying to jump after the ice has starting melting has a good chance of making Mega Man walk into the pit instead.
The next few jumps are much safer, and deliberately melting a block for an item was a good use of these. While the player will be unable to escape if they let the ice under the item melt past the first stage, it is more fair here since doing this isn't required, and players should be better able to anticipate that trap since their knowledge of how the ice works is required to get there in the first place.
Scworm is our next returning enemy, and while its behavior is roughly the same, they're more dangerous in this game's confined space. This is a place where the way momentum hangs around after running into a wall can be a problem, potentially causing players to run into Scworm when trying to jump and shoot from the corner below it. We can also see a Suzy at the edge of the screen, and shooting it from here is preferable to trying to hit it as it moves.
This is a rare case where Suzy is used well. The Scworm is blocking our way to the ladder, and unless we run to the right side and attack from there, Suzy will be taking up space we'll need for dodging, and may block some of our shots. The extra slippery ice helps make this work, as we could easily just kill Suzy before bringing Scworm on screen if there wasn't a high chance of players falling into this area. Scworm is capable of reaching the ledge as well, if a player manages to stop right at the edge.
The following room is a neat little puzzle. We need to get on top of the upper icicles after they fall, either by jumping on the first one from the side, or jumping on the second from the small middle platform. When the third lands there, we can use it to reach the ladder. It's also technically possible to jump from the bottom, but we can use the ladder to reset the room, so there's no need to take that risk.
The next one demands a little more from the player. We need to use the first to reach the platforms, jump to the wall as the second falls, then jump back onto the second, allowing us to use the extra height from the last one to reach the opposite side. Players could also wait on the first one and jump out and around the last as it falls, or (more likely) use the invincibility from taking a hit trying that to cross the spikes.
This is a much better use of Big Eye, as we're always able to run under it if we start moving as soon as we enter the screen. Following is a series of dangerous jumps, with a Joe and two Scworms blocking our way. This ups the stakes with Scworm well, encouraging the player to accurately spread their shots among both parts to keep them from flying onto Mega Man's platform. Moving around on these platforms can also cause a Heli to spawn behind us.
The final three Scworms can be jumped over, which is a cathartic moment after having to spend so much of the stage moving carefully. As a bonus, they can provide easy refills for the upcoming boss room.
The actual design of this stage is solid. It moves from an open combat area to two new types of ice platforms, to a series of harrowing jumps, and a final dash to the boss. Even Suzy is inoffensive here, appearing briefly between more interesting segments and getting at least one chance to cause players some trouble. It's unfortunately made harder than necessary by the sloppy ice physics, and while I would normally liked to have seen one more use of the melting ice before the stage ended, the way it can interrupt a jump turns it into a serious problem.