Oniken is a retro-styled platformer that harks back to the NES era with its visuals, music and difficulty levels. Developers Danilo Dias and Pedro Paiva call it "NES hard", and I'm inclined to agree.

The duo released a beta version of the game recently with three stages to play through which you can download from the official site. There are no cutscenes yet between levels, but all the enemies and level design are there. Give it a try and see what you make of it. (Cheers Thais!)