It's jacksepticeye 's intro. After loud *WWHHIIIPPSSSHHH* (slapping sound) he High-five the air and scream these
words:
"TOP OF THE MORNING TO YA LADDIE, MY
NAME IS JACKSEPTICEYE, AND WELCOME BACK TOOO...(the
name of the game he actually play) (...)"
-in jacksepticeye 's intro, also very often used by his friends (especially pewdiepie) and his fans and all of bosses
-instead of "Hi" or "Good morning" you can
just yell "TOP OF THE MORNING"
-
ATTENTION: you should scream these
words, because it's correct and required way to say it