2010's online game similar to Resizer Game and Spectre Spelunker.

[KLURP-KLURP]

I'm struggling to remember a game I used to play years ago online.
It's a 2D platformer where you have to navigate your way through a maze that gets smaller and smaller and at the end of it you have to escape back out the way you came by getting bigger and bigger. It's doing my head in not being able to remember what it is called...
Please, can anybody help?
Thanks