Sorry, I counted the hidden bosses as sub bosses. The fact that you can skip half the game by beating High Max...
That's not what you said. You said that it affects later levels. Skipping any level does not affect the later levels.
Granted that doesnt involve bosses, but a potentially worse thing, which is just pressing a button. key word is you have to BEAT High max first, and without Turtloid's weapon I think it was, you cant. so X6 requires beating 2 bosses to reach the final stages, (3 if you count the intro boss) whereas X5 just 1 intro boss and the press of a few buttons as soon as you reach the stage select.
It's not any single weapon that's required to beat High Max, it's literally any special weapon X has that deals direct damage, ammo permitting. And technically you don't even have to do that; if you're willing to farm for power-ups without defeating the bosses, you can very easily beat X6 without obtaining a single special weapon.
Zero's a little pickier (his Yammar Option doesn't work for some reason), but the same concept applies.
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