Unamused Slytherin here.

She had basically been right about the castle and she wasn't getting credit for it? What a rip off! No, seriously. Instead, they were learning a charm that EVERYONE IN THE CASTLE had to preform CORRECTLY and SEVERAL TIMES and even then there was no guarantee that it would work. They were doomed. Because it was fact that when you got that many people together trying to do the same thing at the same time, something was bound to go very very wrong.

But still, because Layla really didn't want to be labeled as the one who had doomed them all to death even though they already were, she started practicing the charm. Even though she wasn't happy about it and she was sure that shown on her face.

"CAY-lum SAY-pee-OH, CAY-lum SAY-pee-OH, CAY-lum SAY-pee-OH Caelum Saepio." There's a chance all of that may have been sarcastic in nature.