I'm working in my uni's game research lab ("RESEARCH" lab >_>;), and my team's project is to create a one-mechanic game using the Unity game engine by the end of the term. Our team is kind of in contention right now on our mechanic, so we're going back to the drawing board; someone suggested we ask fellow gamers for ideas, so I thought I'd hit CAA.
What kind of interesting gameplay would you like to see in a simple game (think minigames), particularly something that hasn't been explored much? It has to be one specific action or maneuver that can be used repetitively in interesting ways to make a more engaging complete game; examples might be anything from controlling gravity to stretching Luffyesque attacks to Spiderman webslinging to Portal's gun system, just to name a few. We're trying to avoid the pick-stuff-up-get-power-ups-attack-enemies route Mechanic is more important than story or characters or worldbuilding at this point. Also, to give some scope, Unity is a 3D platform with built-in physics and manipulatable terrain, so incorporating those aspects would be best.
Thanks in advance~ Suggestions before Tuesday (yes, very short notice >_>) would be mecha appreciated...