Hi there. I’ve been grinding on Battletoads for about a month now. Awesome game. I’m pretty good at the first 9 levels, but there’s something that’s happened on level 10 I can’t explain and I was wondering if somebody could help me. There has been several occasions where I’ll get to the third rat and he just disappears. When I kick the final bomb, he never shows up. I just end up feeling like I’ve wasted time because I don’t know what to do but reset, because it doesn’t send me to the boss. Is this some sort of glitch and is there anything I can do next time it happens? Sorry if this isn’t an appropriate question for this forum. I’m new. Much thanks in advance for any help.

It's a well-known glitch. Unfortunately you can't do anything with it. But it shouldn't happen really often. Maybe one day someone will find how to avoid it.