During the Frozen Party, penguins can explore the rooms decorated for the party. For decorated rooms only, you can throw snowballs to make the room (or part of it) become icy. But with the heart emote, you’ll make the room become normal.
Here are the normal rooms:
Here are the iced rooms:
The Ice Palace looks like this:
The decorated rooms each have 3 magical snowflakes hidden in it. When you find them all, you’ll unlock a set of items. Click here for more information about snowflake hunting and unlocking party items.