This game is a sort of sequel/prequel to the IFComp winner "The Impossible Bottle" (TIB) by Linus Åkesson. It is an authorized sequel as Linus Åkesson selected the prize from Mathbrush which would be a game made by Mathbrush in the same universe as the winner's game. Mathbrush has done this before with success and once again it is a success.
Whereas TIB had some surreal mechanics with respect to space, The Impossible Stairs has some surreal mechanics with respect to time. Don't take the "science" too seriously. I don't think I have ever seen a story/movie/game about time travel where there were no plot holes, unless the past couldn't be changed. So don't expect a fully consistent time travel game (I don't think they exist) but a game with fun, semi-logical puzzles.
I never noticed any parser problems. On the other hand, the game did not require an advanced parser. So it was as good as needed.
Mathbrush hits the happy-go-lucky atmosphere of TIB spot on.
It seems that the game can never be unwinnable.
The surreal logic of the first game TIB is present in this game too. This game could be completed a lot faster than TIB and the puzzles were also easier, though some of them were a bit tricky. Overall the puzzles were good.
This game is a great sequel/prequel to TIB. Don't expect it to be as good as TIB (hardly any game is) but it is still a worthy prequel/sequel with some good, original puzzles and excellent implementation. Further more, it is written in Dialog (still only a few games are written with Dialog) and if you play online, the user interface of a dialog game is really neat.