The King's Crushaders is a game concept I have been developing in my mind lately. It is a puzzle platforming game where you control 5 knights with varying abilities, and where the goal of each level is to clear it from oily monsters polluting the elsewhat colorful kingdom.
The gameplay is best described as "The Lost Vikings" meets "Candy Crush". You utilize your characters' individual skills to clear the levels, but as an added hazard and puzzle element, you have to be careful where you step with each character as Candy Crush rules apply: If a character lines up with two or more blocks in the same color as itself, it will die and destroy the blocks in the act. This can of course make finishing a level harder, but sometimes the sacrifice of a knight is needed to get past a certain point and clear the level.
Potentially the game would work well as an opt-in multiplayer game as well, though this could screw a little with level balancing.
The banner image at the very top of this post is a mock-up I did of the concept (link to the full image). As I am currently busy with other things and projects, I choose not to prototype it (or develop it) as of yet. But if you are a developer who wants to develop this idea further, feel free to reach out and maybe we can figure something out. I have plenty of ideas to further the concept both in terms of mechanics and story.