Hey! Thank you so much for your amazing comment. The game will be a bit more 'metroidvania-like' after several updates. This is raw version prepared for a game jam. :) I hope to make it a little bit longer in the near future.
Regarding the save: the save next to the second boss is already implemented in the new version. I need to wait until the rating is over so I can update it. There are some other minor fixes as well. :)
The chest can be used to leave items in it. At this moment there is 'perfect' amount of items so you don't really have to choose what you have in your inventory. However one of the updates will not only extend the map but also introduce several new items. Then what you have with you will be key decision to make.