Made by my son and me in about a week during that time I also taught him Lua.
My son is responsible on the level design that will make you suffer. (Suffer because you might reach a level in which the portal will actually kill you instead of teleport you and you will have to find another exit)
I consider the game very challanging.
There are 21 levels in this game. I was able to reach level 3 but my son has reached the end of the game countless times.
Special thanks to @matthughson for "advanced micro platformer" which we used.
Thanks Nerdy teachers for excellent tutorials.
And finally thanks Lazy devs for great tutorials.