The setup was the same like the other Mega Man games: choose one stage out of 8 stages, defeat the Robot Master and use the weapon to defeat the next robot and so on and so on

The boss fights are hard too mainly because if you happen to come unprepared such as say, your weapon meter is nearly empty when you arrive to the fight or you simply don't have the right weapon in your possession, the bosses will make you pay for that, and the regular arm cannon might not be good enough to get the job done either.

Pharaoh Man is probably the hardest robot master of all six NES games, and has a very powerful weapon.

As laughable as that may sound given how many games there are in the series, it's this same train of thought that makes it a very noticeable and serious problem