The letter

Dear, Nightmare, Cross, Error, Dust, Horror, Killer, Lust, Reaper, Geno, Ink, Dream, Blue

Hey guys, It's me...Sci,

So uh, I've just discovered something really cool. And I mean like, really cool. I was wandering if ALL of you could come down to my lab this afternoon so I can show you this thing.

I promise you'll love it!

-Sci-

Nightmare frowned and looked at Error, who had been reading over his shoulder. He simply shrugged in response. "Eh, might as well, I'm bored and we've got nothing to do. What could possibly go wrong?"

What could possibly go wrong...?

Ehehehehe I wonder.