Now to look at some games with a history of being difficult, at least the games they're trying to rip off.

Metagal
It's genderswap Megaman, in fact it looks like it could've been made from an engine designed to make a Megaman like game, unlike Megaman, this game is infinitely easier and the achievements reflect this.
D-Tier Game.

Cyber Shadow
Quickly followed up by classic Ninja Gaiden but with robot ninjas, at least this one feels alot closer to the game it's trying to ripoff pay homage to, but it commits the unforgivable sin of not having achievements that end with 0 or 5, blasphemy in achievement hunting.
C-Tier Game.

Wizard of Legend

Roguelike games will start to feature quite alot in this series and the first of these is the ball bustingly difficult Wizard of Legend, you control a Wizard of any colour you want and take out some of gamings most difficult bosses, fast paced and frantic, it's up there with some of the best of the genre and the only game where I can actually play a "Cerulean Wizard".
S-Tier Game