minecraft wiki says this: Notch added a small chance for Ghasts to spawn in the Overworld near Portals in Beta 1.5[1]. A Ghast spawned outside of the Nether will fly everywhere, mainly above the clouds. Can even spawn extremely rarely without a portal but, the amount in the picture is likely too much for even the small chance EDIT by Moderator: merged posts, please use the edit button instead of double posting.
Yeah, I agree, and they are in one line (wtf?) Oh yeah, they can't hurt you or be killed, they just make EXTREME NOISE! EDIT by Moderator: merged posts, please use the edit button instead of double posting.
Lemme check Nope, still there. EDIT by Moderator: merged posts, please use the edit button instead of double posting.
Zombie Pigman is there probably because there was some lightning that struck it. If there wasn't, glitch/bug.