As the tagline for the Kickstarter video says: "How is this not a thing yet?"
Sensors in the hilt communicate between swords, differentiating between blade and body hits and even allow for a range of game modes:
ONE HIT TO WIN IT
Self explanatory. Land one successful body hit, and you win.
Land three hits to win.
The stronger the blow, the more damage your opponent takes.
Identical to Countdown, only you can earn health back over the passage of time, or by blocking several blows.
The name says it all. Identical to Eternal Struggle, only you can earn health back more quickly, and with even fewer blocks. Also, the lower your health gets, the less damage you'll take.
At the moment it's only one-on-one fights but multiplayer's promised along with shields and armour "around the corner".