MONOVANIA was created for the Metroidvania Month 14 game jam. Its source code is freely available.
Players start the game with the ability to rewind time.
The objective of MONOVANIA is to collect the three exit keys and make your gray-t escape.
What is a Metroidvania video game?
Metroidvania is a subgenre of action-adventure video games focused on guided non-linearity and utility-gated exploration and progression. The term is a portmanteau of the names of the video game series Metroid and Castlevania, with games in the genre borrowing from both series.
-Wikipedia