Most of the systems for collisions and agents and whatnot were premade (since I use them in basically every project I make), so the actual content only took about two days - I spent most of the jam just hemming and hawing over what mechanics to add. The basic player movement and the mechanic of bomb-laying were made on the first day in about 6 hours, while the biggest main level, all of the sounds, and the music were made in the 4 hours right before the deadline.