Thompson completed the hat trick at 15:58 with a dangle in the slot to make it 7-3.
"It's enjoyable to watch 'Tommer,' having history with him, watching him when he was 16 years old, watching him grind his way to this point in his career," Sabres coach Don Granato said.
"The thing that sticks out is the excitement of the bench and the players around him. It really tells you the person he is. … To see that and see a kid that it took so long for him to flourish and be recognized for the talent that he is, to see him fight through that and now start to get rewards for that work, it's definitely enjoyable."
Thompson, who factored into each of the final three goals (two goals, one assist) in a 4-3 overtime win against the Chicago Blackhawks on Saturday, become the second player in Sabres history to have a point on eight consecutive goals since Pat LaFontaine in 1992-93.
"I didn't know about that stat, but it's pretty cool," Thompson said. "Obviously, he's one of the best to play the game, so to be mentioned in the same breath is a pretty cool feeling."
Rasmus Asplund scored with 39 seconds remaining for the 8-3 final.
"We hung our goalie out to dry tonight, which is, that [stinks]," Copp said. "They make it 5-3, OK, 6-3, but you can't let it go past that. Just unacceptable."
NOTES:Thompson became the sixth player in Sabres history with six points in one game, and the first since LaFontaine on Feb. 10, 1993 (one goal, five assists). His hat trick is the 22nd in NHL history on Halloween and the first since Michael Frolik of the Calgary Flames in 2015. … Okposo has multiple points in consecutive games for the first time since Jan. 9-18, 2018 (three games). … Larkin scored his first short-handed goal since Oct. 30, 2018.