By the sounds of it, are you thinking of "Heart of Darkness", at the beginning, you was sucked into a black hole type thing and you ended up on a mountain, your a boy and you start of with an electric lazer thing, its in 2D and theres black creatures that come from both sides, if they get close they eat you in one hit, the first level in on a mountain, but later on you end up in a jungle area and water areas. sound familiar, i dont know if it was on N64, but it was out for ps1 and had 2 discs and 3D glasses, because the last cutscene was in 3D. o yh i think it all starts because someone steals your dog, so you go to the land of darkness to find him.
