Games by finnish indie game developer Adventure Islands with a focus on retro style games with great pixel art.
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Imo, the best "hidden gems" dev. Actually, at this point, he isn't even hidden xD He has a huge fan base
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Dadish is awesome (+you can test it and on your phone for free, it works equally well on both mobile and steam)
There are 3 dadish games in total
MagiCat is a side-scrolling platformer inspired by the retro games from 16-bit era. The game features a cute magical cat adventuring 63 levels, each with their own unique boss battle spread across 7 worlds.
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Cats.. Duuuh.. xD Jokes aside it is very well balanced