Quick gameplay view of an assassin ab build. Did only 2 games with it, and I must say, it's kinda good, but you don't have any self heal at all. So if your spike fails, you will have to run for your life, or have a good monk behind you (which I had).
Pro's:
Quick Spike
Can Double knock down
If spike is timed good enough, and the foe has no anti-block, there is a 99% chance of winning a 1v1.
Con's:
No selfheal
If foe is casting a skill at the beginning of the spike, the spike isn't perfect and
If foe is near an ally, the second knock down (and also the spike) won't work.
No run-skill