Added three levels

Good evening. Today I created some levels for this game and added Sound Effect for jumping. In my opinion these levels can be too hard and too easy at the same time so... It will be helpful if you write what are you think about them.

Changes:

• Added three new levels
• Added ONE (1) sound effect and volume slider for it
• Added pause menu on "ESC" key. Idk why.
• Fixed some bugs (You can't fly now, sad for you)

I guess now this project can be called a game. But it's not fun enough for me right now. I'd like to add some features. Maybe some interactions between normal and reflected slimes and some gates... idk... I should have enough time for at least 2 more levels.