One type of ice breakers are connectors. They can break the ice when meeting with strangers the first time.
There is another situation. She had a bad day at home, and was criticized by her boss at work in front of other colleagues. She could not help, but nastily fight back with her boss… and then she realized what she had done.
She run away from work, hided for a few days.
She came back and was shocked to find her boss treated her friendly, explained to her the situation and apologized to her.
She was embarrassed, felt guilty for what she had done. But her boss broke the ice and had moved on.
Her boss is a brave person, a generous person and a kind person.
Being an ice-breaker needs skills, courages, and generosity.
Ice breakers do not have big ego.