I'm an assasin myself that has gone through multiple resets just to look for what comforts and fits into my play style. One things for sure, if you want to go bosshunting and create an output with the best and fastest damage, you need to be in a party. As I've read by another fellow Assasin in a different thread, "Assasins weren't meant to solo. Ninja's are."
Yes, it's possible to boss hunt alone and backstab alone. It took me about 1-2 weeks to perfect maneuvering my character when boss hunting alone to backstab. I'd wait for the pause in the enemies attack intervals and move behind them to backstab then continue to attack until my BS cools down then rinse and repeat.
As for your gears, it will depend on your situation. Since there are three styles of backstabbers (str/int/crt)(int/dex/crit)(int/str/dex). Some assasins throw in some agi and vit. That really just depends on you. Again, a fellow assasin also said on another thread that agi does become detrimental later in the game but you can certainly work with agi (about 120 agi) using evas equips to solo boss hunt but you won't exactly get the best dps since you'll be investing your equips or crystas in evasion.
Since you're soloing bosses, I'd recommend staying with T.Knife Up since it adds evasion. If you're with a party and you aren't the tank, then go fuma shuriken.
Exelis up is a nice pick up if you aren't gonna be taking up a lot of dex for your backstab but if you will be investing stats in dex, I would go for other armors that may increase your atk and/or crit dmg / chance. A cheap armor that would work for pt boss hunts would be a dunk/schwartz especially if you have invested dex.
Wolf ears is an "okay" add gear. It's not the best if your tank is a ninja because if you invest in dex and spam your bs pretty fast, you might pull agro. I'd know. This happens to me a lot. If your tank is a paladin, that wont be an issue though. A good alternative would be Horned Helmet Up because of the atk percentage and the 5 vit. I'm also saying this because I'm assuming you have some stats invested in crit so that'll add more damage.
As for your special equip, you could do that but if you can't afford it immediately, I'd get a simple Atleta ring or if you're soloing bosses you could go with an Sbangle to increase your chances of tanking any incoming hits though I think you'd still get one hit with the latter bosses. xD
The best advice I can give you is figure out what your favored play style is first and build around it (Stat wise and gear). I ran into Flarius not too long ago and have been reading his guides; his words of wisdom ingame helped me find my favored build that works for me and now i'm happy with my assasin and don't need to reset anymore. Good luck and more power to us assasins. :]
TLDR; Find your favorite playstyle and build that works for you. You're on the right track with gears.
Guildmaster of Assassination
