Avatar: The Last Airbender S03 E09 Nightmares and Daydreams

"Water. Earth. Fire. Air."

Four days prior the invasion, Aang becomes nervous over his soon-to-come confrontation with the Fire Lord. His anxiety gets the better of him as he begins to suffer from outrageous nightmares and hallucinations. Meanwhile, Zuko becomes upset to learn that he was not informed about a war meeting.