I liked how Battletoads made you think it'd be an awesome co-op game to play with a buddy, but since 90% of the game was insta-death platforming that meant that 2 player mode was just an extra chance to screw up.
The odds of two people who could beat Battletoads also being friends were infinitesimal.
I think this game actually used part of the Blaster Master engine. Which in itself, was originally about a space fight and aliens, etc...which then somehow got translated into "Jason's pet frog hops down a hole which leads to a cavernous radioactive evil monster underworld which is in Jason's backyard for some reason*. Jason then finds tank with wheels that look like Children's Tylenol and goes after his frog through eight levels with music that starts out great and gets progressively worse."
I don't know what they were smoking over at Sunsoft.
(* It is possible that he lived next-door to Alex Roivas.)
I remember playing this as a kid and thinking "Wow, this has NOTHING to do with the Addam's Family." Apart from a Fester sprite, the game literally could have been with any generic character or story about stopping evil monsters.
I almost beat this game, but a family friend decided it was too dark in the room and decided to flip the switch. The nitnendo was on that circuit and my game got turned off.