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I was wondering how easy it is to create a game like this:
1. I wanted to make a game where a player could "walk" on a planet (planet will be small enough that the player could walk around the planet in short amount of time) in clockwise and counter-clockwise direction
2. The player could jump out of the planet, pushing the planet in the opposite direction where the player is jumping towards to
3. Player could land on a nearby planet and when it does, the planet gains the momentum that the player carries and moves with the player. While player is on the planet and the planet is moving, the player can move around the planet and jump, repeating the process.

Is it too hard? Should I make heavy use of 2D physics? What do you guys think about this concept and if you have any ideas, please share how you would tackle something like this. Thank you.