All the assets are made by me, during the jam. That's why there are so few levels, they take about 2 hours each to create! The art and coding has all been done by me, and the music and sound effects by a friend of mine, GreaterPangolin, also made entirely during the jam (:
here is the basic tileset i made, if that can help (: actually now that i think of it, the idle animation of the green character and the grass tile were made a couples of days before the jam. But those are the only ones