For the attack chain I got the idea from the traditional BoA sin. I also wanted to keep the Shadow Step and the faster attack speed which both made the BoA Sin the ultimate killer.
The problem was that I did not have Shadow Prison on my PvE Assa and I also wanted to have something new. That's how I got the idea for this Build.

Attributes and Skills:

Armour, Weapons, Runes and Insignias

Armour
Use Radiant Armor to have at least 30 energy.

Runes and Insignias
Headpiece: Assassin Rune of Superior Critical Strikes / Radiant Insignia
Torso: Assassin Rune of Minor Dagger Mastery / Radiant Insignia
Hands: Rune of Clarity / Radiant Insignia
Legs: Rune of Major Vigor (Superior or Minor) / Radiant Insignia
Feet: Rune of Attunement / Radiant Insignia
As you can see I have 16 Critical Strikes and 13 Dagger Mastery.You can change this. It might be better to use two major runes and then use the Attribute set: 14 or 15 Dagger Mastery and 14 or 15 Critical Strikes. This will depend on your Mask.
But as the whole combo takes 55 energy and your energy will depend on Black Lotus Strike, your critical attacks and your Zealous Daggers it might be better to use higher Critical Strikes for a greater chance of critical and also to increase BLS's energy gain.


Weapons

Ceremonial Daggers
Piercing Damage 7-17 (req. 9 Dagger Mastery)
Damage +15% (While Health is above 50%)
Energy gain on hit: 1
Energy Regeneration: -1
Health +30
Instead of the +15% damage mod you can use + 15% while Enchanted aswell.

Template

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How the Build Works

1) Be sure you do not have any anti-melee-Hexes on you (Insidious Parasite, Empathy etc.) and that the enemy did not cast any spells on him or put any spirits down that could make your spike unsuccessful(like Aegis,Displacement, Shadowsong etc.)
2) Use Mark of Instability then immediately follow up with Aura of Displacement[E].
3) UseBlack Lotus Strike. During this action, when you hit your enemy you should push Tiger Stance.
4) Use Twistling Fangs, Falling Spider and Blades of Steel to finish your target off.
5) Come out of harm by deactivating Aura of Displacement[E].

Note: As you can see this Build does not use BoA because it only lasts 2 seconds. That’s why I have chosen Tiger Stance that lasts for 4 seconds which is enough for your combo.

A bit philosophy about the Build's assassination
With this Build you can spike down almost any caster in a few seconds so that during the spike he cannot even use a skill to hinder your combo except stances.
If you plan to kill a Monk you should consider some of my thoughts.
There are 2 basic Monk types it the game. Into the first category belong those who see the Assassin coming and prepare before you arrive to spike them down. These are the good Monks who always have an eye on the enemy team's Assassin. To the other type belong Monks that do not see you or just do not care about you because of something. If your target Monk belongs to this group it will be approximately 80% that you will kill him. The other ~20% happens if your Monk has Hex Breaker, Aegis etc. on him or there are spirits on the field which are very common nowdays. If your spike does not success because of one of these problems you should just come out of harm and wait.
Let's imagine your target belongs to the first group of Monks who actually sees you. He might makes Guardian on him just in time. In this case don't attack him. If he only used Reversal of Fortune then you would go and spike. He would survive but with very little health and with the help of your teammates and your normal attacks you can finish him off. If not and you are attacked, then again shadow step out of harm.
These are the cases if you plan to kill a Monk. Let's kill someone else. If your team is attacking heavily you have to charge in aswell and use normal attacks on someone(maybe on the Monk). He won't care attention to you if you do not use attack skills or if he just saw you using your whole combo on someone. But when his health is about 2/3 he will start to use skills like Holy Veil and Guardian on him to protect him. If you think the Monk is caring to much attention on himself then you can just pick another target and spike him down and your Monk just won't be able to do anything.
Warriors, Rangers and Paragons should be avoided though because they have higher armor and can have defensive Stances that can hinder your spike.
Ok, this was tough I know. Just wanted to give some advices about fightning.



Variations / Pros and Cons / Counters

Variations

For the Alliance Battles you should use Dash instead of Resurrection Signet because there you will be automatically resurrected
Another variation of the Build is to use Assassin’s Promise instead or AoD. There you have to switch Mark of Instability for Dark Prison and Falling Spider for Black Spider Strike. This combo allows you almost the same damage (Black Spider deals less damage than Falling Spider) but with no knock down and with no escaping ability. But you will get your energy back and your skills recharged after the successful combo because of Assassin’s Promise. That’s why you will be able to use your spikes just one after the other.

Pros and Cons

BoA Sin
No Blocking if using Expose Defenses
Can slow target by 66% hindering his escape
2 Hexes which are not as easy to remove as only 1

My Build
Knock down during the spike hindering escape and the usage of defensive skills
Better damage bacause of Falling Spider
Can Shadow Step out of harm
And the last point: there was no SP Assassin who could beat me in 1 vs. 1 but I could kill many of them.

Counters

Anti-melee Hexes
Blind
Defensive methods(Guardian, Whirling Defense, etc.)
Hex Breaker
Enchantment removal


Conclusion

Thanks to the author of the original BoA.
Thank you for reading.