The Book Of Quirk Malfunctions!

3 (Shoto Todoroki)

Todoroki is practicing his ice quirk and makes a huge, thought to be sturdy, ice wall. Before Todoroki can process the situation before him, the ice wall breaks into pieces and comes falling down on him. Once he does realize, he makes a dome of more ice, which is quite sturdy, until the ice begins cracking as more and more fractions of ice fall down on it. Eventually, while Todoroki is trying to figure out a way out of this situation, the ice dome breaks, and he's crushed by the ice.