A big group of us are taking part in Ludum Dare together. We had a Breakfast and Brainstorming session this morning (9am UK time), then split into about half a dozen teams and a few solo entrants.

Our team (@Binney, @Scoobyben1, and I) are working on the idea of "keep the tune alive". The player is in charge of a marching band of cute mice, who need to make it through their whole tune and march to the end of the level. Obstacles or events in the level can cause individual mousicians to go out of step or out of tune. You need to help them get back in time/tune. If a mousician is out of time/tune for too long, a bird of prey swoops in and carries them off (presumably for a sternly-delivered music lesson).

We're also using Ludum Dare as an opportunity to learn Godot, which seems to be a really good fit for this game. Here's our first level in the scene editor...