Depends on how much patience you have.
I have done it, however nowadays I go minimum base 30 Intelligence even on my Barb and so on... but this is for Solo and healing, not casting vs Sneaky... I prefer to ignore it altogether since update where it will spawn, and you exit game and recreate game and that objective doesn't appear again... what is the point of X points to vitality if you are level 55+ killing of sneaky... pointless.
Oh, as I stated, I used to do this, it worked, however it took a long time to kill, even though regen mana in town is faster than regen your hit points, thus you enter catacomb more frequently.
Test it for yourself, see if it is worth it, also, you don't need a person to enter game and kill it off for you at like level 55+, the rewards is pointless, you should get this objective done by level 20 minimum to reap the rewards.