The first thing that caught my attention is a leaderboard. A leaderboard??? In a game jam game?
Anyway, on to the game itself. A very simple game about reaction, hand eye coordination, and timing. You click on the correct bombs, and avoid clicking on the other one. After a while, the placement of the bombs got switched. The longer the game goes, the faster the switching becomes.
A strategy that I found, especially at a later stage, is to just focus on one bomb. That's how I got a pretty high score. I think it would be better if the switch speed gets impossibly fast at the end, so it forces a game over. Therefore, the player has to act quickly at the start to get more points, before everything gets too fast.
I think it would be a good idea to add the final score at the game over screen. Sometimes I forgot to check my score before the game over screen.
The art is also simple. It gets the job done. Maybe a little bit too simple. I think some additional art would be good, such as a background. A simple one would do.
Unfortunately, I fail to see how this fits with the theme. I guess it fits the "reaction" part. You have to click in succession to get a high score. So I guess that's where the "chain" comes from? An interesting take on the theme.
I also found a bug? All of the sound gets a lot louder and more glitchy after a while. I'm not sure if this is intentional or not. When you get far into the game and you click on a wrong bomb, the sounds are ear piercing.
And yes, as other people has said, the leaderboard is a little bit broken. I got past 50 before, but it said I only got up to 47. Not really a big deal though. Another thing I may add is with the addition of the leaderboard, the replayability skyrockets xD. It's fun to compete with other players and see who can get the highest score.
Sorry for the long comment. I like to ramble a lot when doing these kind of thing.