I really wasn't feeling the assassin class early on, kept getting absolutely destroyed by most of the bosses and even regularly enemies were giving me a really hard time. Just felt really under powered and under armored. At least part of that was just getting used to playing as a different class than usual [my go to for DS1 and DS2 was classic sword and board paladin or similar]. But lately I've learned to love the estoc. There's just nothing quite like the feeling of blasting through an enemy's shield with a lunging stab and then unloading a barrage of jabs that leave them staggered until I finally run out of stamina. The main thing is you gotta be patient and look for the opening between attacks, then just unload until your stamina's gone. A lot of enemies can't break free at all because the attacks are too fast.