I think that's just the name of the type of weapon she uses, it's a type of ice that freezes everything it touches
Mouse man has also returned to New 52 as a mouse called Mauschen, the writer didn't mention it in the book and only later confirmed it on twitter, so it went unnoticed (plus it was a really small part, plus it was only Mouse man lol)
But his new design is ADORBs
"Not the finest meal, but better." Did Killer Frost just EAT Mouse Man, in this story?
No, no, no, no, no-ooo, chica. Leave the tiara, on. I like it, on. Now...u-uuh...lift your leg, a little.