The enemy troopers you fight in the research center are very similar to the basic enemy troopers in Gunstar Heroes. They have similar costumes and combat behavior.
I've heard that in addition to being much easier, the Japanese version gives the different player characters their own lines, when they have dialogue. I don't know if that's true, though.
I'm pretty sure Schneider's frequency is something you don't get told in-game, and you can only get it from the manual. Back when I played this on the NES, I found it by methodically checking every frequency.
@kabhukiman: Brad (the wolfman) has a slightly larger than normal hurtbox and no homing weapons, but he makes up for it with the fact that his shorter range are INSANELY damaging. He's a character for daredevils.
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