Right from the very beginning of the Krakoa era, we've seen several characters take up new codenames. But how likely do you think they are to stand the test of time and stick?
Fabio Medina - Egg
Fabio went from Goldballs to Egg, which wasn't a great improvement admittedly, although Egg perfectly describes his role as part of the Five. But the moment resurrection is no more, I fear the new codename, and probably Fabio himself, are easily done.
Jean Grey - Marvel Girl
The first new codename introduced in House of X, and the first one to be gone, along with the new/old miniskirt. Still, the WildC.A.T.S's Grifter clearly had an appreciation for it, so here's some smootching courtesy of Jim Lee.
Jamie Braddock - Monarch
This was first introduced in the HOX Omega mutants info page and, to my recollection, never really referenced again. Not a bad codename mind you, but what use does Jamie have for it? Or clothes, for that matter?