It seems like it's been a long time since I've shown a Game Boy game, and even longer since I've shown a pirated Chinese original. Lei Nu Ji Shen (perhaps also known as "future robot") stands out from the usual Chinese crowd, avoiding most of his common flaws.
As far as I can tell, while the look of the protagonist (and the game in general) is definitely heavily influenced by the 90s mecha anime, the setting is original. The visual presentation as a whole is of a particularly high standard, with good backgrounds and detailed sprites. There are also some amazing looking full screen graphics for the intro and ending, as well as for the static screens after the boss. The music doesn't match the looks though, being a high-pitched, squeaky cacophony.
The game itself is also head and shoulders above the norm, as the controls are hard, if not original, and the game is actually on a gaming difficulty level. How your robot plays is the same as Megaman: he can jump, he can fire three normal shots or one charge shot, and he can dash/slide by pressing down and jump together. The only addition is that the robot in this game can also double jump. There's even a simple animation, which is another way Lei Well Ji Shen shows off the extra bit of polish he has above his peers.
The stage design is unfortunately the weakest point of the game after the music, as each stage consists of walking from left to right while constantly shooting and occasionally jumping over a bottomless pit. Even combat is boring, as there is rarely more than one enemy on screen at a time. The bosses add a bit of variety, although the stages between them seem incredibly long.
While Lei Nu Ji Shen is, as I said, much better than the regular pirated original, especially the ones that appear on 8-bit consoles, I can't recommend it. Even though it looks really cool, it's just not very fun to play at all.