Don't worry about creativity. Instead, worry about how well the sprites do their job. Creativity often comes from solving the problem of things not doing their job well enough.
For example, it looks like you want pretty thin limbs, but how well would they read against your game's backgrounds? (Tip: if you don't have some art of how the background will look, get on that because it's very difficult to make effective sprites for a game without context.)
The black swirly and red antler creatures look like they belong in the same game, but the other creatures look like they belong in other games. What design changes could you make to feel like they belong together? If the art doesn't feel like it belongs in the same game, that is a problem to solve.
What is the story you're trying to communicate about each character with their design? If there is not a story, then what idea? Are the creatures friends or foes? I feel like I am looking at a bunch of random ideas that aren't trying to communicate anything to me as a player. What are the things the player should be able to tell from your design? How can you make those things clearer in the designs?
Figuring out what problems you need to solve is the first step to being more creative. Creativity doesn't happen in a vacuum. Hopefully the questions I posted will help guide your thinking in a useful direction.
Always keep the player in mind. What does the player need to know to understand and enjoy the game? How can you communicate that through the visuals? Often, it's possible to communicate much more than you might initially imagine, making things like text dumps about the setting/story and mechanics unnecessary.