Definitely the 2014 Championship between Seattle and Green Bay.
I remember the Packers being ahead significantly, and I was sure they would win, I mean after all how hard would it be to make a comeback against a team with Aaron Rodgers as quarterback? I was joking with my dad "Wouldn't it be crazy if Seattle came back and won?"
It was 19 to 7 in the 4th quarter..Then Wilson threw his FOURTH interception of the day,, giving the Packers the ball at their 43-yard line with just over five minutes left in regulation. Game over right? However, Seattle's defense made a crucial stand, and gave up TWO timeouts.. Seattle then got the ball back starting on their 31-yard line with 3:52 left. They marched down the field efficiently for once in about 3 big plays and Wilson scored on a 1 yard run- making it 14 to 19. Game over still right? I told my dad "what if they actually got this onside kick? Wouldnt that be crazy?" and sure enough THEY DID. The legendary onside kick that bounced off Bosticks helmet and into a receivers arms. A few plays later Lynch scored on a 24 yard run with 1:25 remaining on the clock to make it 19-20... they went for the 2-point conversion and Wilson was flushed out of the pocket, ran backwards with absolutely no hope and LOBBED it back across the field and it fell right into Luke Wilson's arms, who was never supposed to be an option on that play! making it now 19 - 21. Rodgers did his thing though and marched down the field to tie it up with a field goal to bring it into overtime..
Seattle won the toss, and after a few quick big plays, Wilson threw it up to Kearse who was running straight down the middle of the field while TIGHTLY covered by Tramon Williams but still managed to pull ahead of him just enough to make the catch for a 35-yard touchdown reception, beating the Packers and keeping them from going to the Super Bowl.
My dad and I cheered as if the Vikings won a big game. It was absolutely unbelievable.