As far as i can tell, i have not played anything else like this in the jam. So great work on making something unique.
Now I will start with presentation, the games visuals are simple and clear, the ghosts all have good color choices that make them stand out, and better yet there is a behavioral difference between different sizes and colors of ghosts. Having ghosts with different behavior look noticeably different is very good and makes the situations easy to read, so really good work on that. In regards to the sounds they were all there even the sounds for throwing the dice, dice landing, ghosts getting hit, standard ghost noises etc. Better yet none of the sounds overpowered each other or the music. Speaking of music, it fit the game well, and i liked it. All in all from a presentation stand point good work.
Now for the gameplay/game mechanics: The idea of actually using the mouse to throw the dice was clever, the idea to make the mouse the vulnerable player, even better. I liked this idea and it forced me to really control how much i swung my mouse around. Admittedly, I often threw my mouse into ghosts with the die haha. Overall i like the mechanic and i think it felt punchy and good to throw the dice this way in part because of the good sound design but also because it was momentum based. My one bit of feedback, is you may want to lock the player mouse or some representation of it within the parameters of the game. There is an exploit where the player can hide the mouse outside the window of the game and lure the ghosts away from the dice so that the player can than quickly return.
All in all, this was a fun game, and I enjoyed it. Thanks for sharing it.