Shoto uses his ice powers to create a massive ice ridge in order to either freeze or block his opponent with its large size.
He can control the size of the ice wall to some degree. When he used this technique against Katsuki Bakugo, Shoto created a much more controlled version compared to when he attacked Hanta Sero with it.
After his quirk training under the Pussycats, Shoto was able to produce a massive ice attack against Mr. Compress.
The major drawback of this move is that it drops Shoto's body temperature to his limit immediately after it's released.