It's a mixture of Zero and X mechanics from the Mega Man X series and some aspects that resemble RPGs, sidequests.
The game is a little short as I remember, but it's fun and I liked to attack with a dash-slash, I wasn't afraid of taking damage and I died a lot.
The story is interesting in this game, the game ends like it's the last one, but it's not true and I appreciate that.
The soundtrack isn't very good, the only one I like is the intro track.
It is not that hard.