You will need to supply your own blue character for the effect. It says (in the guide I provided) to reduce your character sprite to 6 colors, and I even gave you the colors to use for it to have the best look. But you don't need to use it that way, you can do whatever you want, you are a creative game developer with the power of programming at your fingertips 👍
There's no special ground animation or any intended mechanic for the frozen character sprite. You can use it however you like. Maybe a weather effect, maybe a spell effect, or story effect, whatever. You will need to code all those circumstances according to your need, all I am providing is the art.