welcome to the world of creativity with C2!
I can see you get a first impression using the C2 framework.
It's a good start to use tutorials and build up your ideas.
You could add some audio - creepy background music and sounds to give it an ambiente.
Also a shadow (simple shadow sprites*1) for the player and enemies will give it a 'depth'.
*1: make a grayscale version of the sprites and pin it below the player/npc.