Assassin/Ninja Good Assassin Build Suggestions?

I'm a level 65 assassin. I don't really know much about the game since I've been gone for 3 years, but I would like to reset my skill points, as I feel they are not the best for assassin. The points are as follows:
Strength: 36
Dexterity: 14
Intelligence: 37
Defense: 37
Agility: 38
The weapon I use is "Olux's Prized Dagger", though I have gotten a couple new ones that don't seem as good so I sold them.... maybe wasn't a great idea. I want something that will deal a ton of damage and tank, so I'm guessing defense and strength should be upgraded, but I am very open to suggestions. Thanks

 

For your level I would just invest into intelligence and whatever stats your gear needs. You don't really need a build until you're max level.
https://www.wynndata.tk/mana/ ---> Int required to decrease spell cost.

 

im late but thought i'd link this thread since it might be relevant to you
afaik olux is fine