Super Mario Bros. 3 (U) (PRG1) in SUBNESHawk.
Reaches end cutscene. Has invisible credits though.
Explanation
Due to the DPCM glitch, a workaround was programmed into the game. It consists of rereading inputs until two consecutive inputs match. This can be abused by constantly changing input, leading to an overflow.
Input
____Input LogKey:#Power|Reset|#P1 Up|P1 Down|P1 Left|P1 Right|P1 Start|P1 Select|P1 B|P1 A|#P2 Up|P2 Down|P2 Left|P2 Right|P2 Start|P2 Select|P2 B|P2 A| |..|........|........| |..|........|........| |..|........|........| |..|........|........| |..|........|........| |..|........|........| |..|........|........| |..|........|........| |..|........|........| |..|........|........| |..|........|........| |..|........|U...S..A| |..|........|U...S..A| |..|....S.B.|........| |..|....S.B.|........| |..|........|........| |..|........|.D.RS.B.| |..|........|U.L..s.A| |..|........|.D.RS.B.| |..|........|U.L..s.A| |..|........|.D.RS.B.| |..|........|U.L..s.A| <45 repititions of those 2 lines> |..|........|.D.RS.B.| |..|........|U.L..s.A| |..|........|.D.RS.B.| |..|........|U.L..s.A| |..|........|.D.RS.B.| |..|........|U.L..s.A| |..|........|U.L..s..| |..|........|........| |..|........|........| |..|........|........| |..|........|U...Ss.A| |..|........|U...Ss.A| |..|U.L.S.B.|........| |..|U.L.S.B.|........| ____/Input