User blog comment:Master Sima Yi/Assassinews 19-03-'14 – Two Assassin's Creeds for 2014?: Unity and Comet/@comment-2142534-20140609195854

I'm not sure, but I haven't noticed double hidden blades. There is are double assassinations in the gameplay a few times, but they do it with only the left blade. If it's true, then there will be some cool new moves, killing two guys with one hidden blade.