Giana SIsters 2D is a remake of the original Giana Sisters game for the C64. This released on Android, iOS, PC and the DS. I first experienced this game on Android in late 2017 but didn't fully complete it until earlier this year via Steam.
Giana Sisters 2D takes place in Giana's room where Giana is currently asleep. The treasure chest suddenly began to burst out with magical powers. Woken up by the light, Giana chases her diamond collection into the darkness, which made her end up in a magical world. She then goes to collect the diamonds back and discover the secrets of this magical world.
So Giana Sisters 2D essentially plays like a Super Mario Bros game; you run, jump, defeat enemies/bosses and get to the end of the level. The only power-up is the red ball which transforms Giana into Punk Giana, who can throw fireballs. The game's controls are responsive and it is fun to go through all the levels.
There are 8 worlds, which all have secret levels if you collect all the Red Diamonds in every level. The bosses in this game are uh... meh. The only boss you fight is a fat green dragon who has more health and attacks as you progress through the game. I mean, it's not bad I guess but I would have liked a little more variety.
There are two main problems with this game though. For one, the level design can either be on the bland side or really dickish in the later game. The issue is compounded when you have enemies which are placed in questionable positions, making the late game an absolute nightmare for me.
Otherwise, Giana Sisters is a fun little Mario clone, which has its problems, but it is still a good time. It is a short game, so I recommend buying it cheap. Preferably the smartphone or Steam version as the DS version... is expensive as hell.