I made this build in the preview and I haven't really tried it lately, but it should work fine . This build may vary depending on how you change the skills, so the attributes may change to whatever fits your build or depending on your runes, but the purpose of this build is constant enchant stripping and provide some damage so I recommend keeping Critical Strikes high.

A/W
Attributes:
Dagger Mastery: 11+[1-2], 12+[1-2]
Deadly Arts: 6+1 (if Dagger Mastery is at 11 and your not using Shadow Arts)
Shadow Arts: 6+1 (if Dagger Mastery is at 11 and your not using Deadly Arts)
Critical Strikes: 12+[2-4](Mask+Runes)

Skills: With Dagger Mastery: 11+[1-2] and Deadly Arts: 6+1
Iron Palm (the knockdown can help and a little damage if you use Deadly Arts, you can change it to something else if you like)
Fox Fangs
Critical Strike (or use another Dual Attack if you feel your critical rate is high enough)
Wild Blow (If your not a A/W change this to something else)
Dark Apostasy (This build Depends on this skill)
Critical Eye
Siphon Speed (use with Deadly Arts, may change to something else)
Resurrection Signet

Wild Blow is important in this build as it can't be blocked or evaded, it results in a critical hit, removes any stance, and also has a quick recharge time for quick use, so I highly recommend A/W for this build :up:.
If you have another secondary profession, you can try using Expose Defenses or Way of the Fox for enemies using stances.
You can use Shadow arts if you would like for some self healing or support.
Combos can be change to whatever you like the most, but I think Iron Palm as a starter is nice because of knockdown (if the opponent is hexed or has a condition) and the fact it's a spell means it can't be blocked or evaded from stances which will lead to Fox Fangs which also can't be blocked or evaded.

I think I got most assassin skills but I may change it later if I or anyone has a better suggestion, so don't be afraid to post .

P.S. Does Dark Apostasy work against Reversal of Fortune spamming? Will it remove Reversal of Fortune first then calculate the damage? Thanks .