How to play:
1) Click to start game
2) Click to start round
3) in each round, wait until the "FIRE!" signal is given, then swipe with the mouse to fire. The direction and length of the swipe will set the angle and force of the bullet.

More info:
I wanted to avoid doing anything time-based, as that seemed a bit obvious. Instead, I took "seconds" to mean the people that sometimes accompany combatants to a duel. In my game, the player takes on the role of a person summoned to duel (pistols at dawn, of course). This particular duel allows each party to bring up to five seconds along, leading to... 10 seconds on the field.

The seconds themselves don't directly participate in the duel, but they can catch bullets, making it harder for the combatants to hit each other.

Gameplay consists of rounds where both the player and AI opponent fire a single shot. To fire a shot, the player must swipe with the mouse (web) or finger (tablet), which sets both the angle and force with which the bullet is fired. Firing before the signal is given is poor form, and will not count. Any seconds that are hit are killed. This continues until either the player or the opponent is hit.

I wrote the game in HaXe, which means that it can go to multiple platforms easily. I find it a lot more satisfying to play on my ipad, as the swipe-to-shoot mechanic is much better on a touch screen, but I've also created a SWF version for ease of sharing.