What is the base regen for life essence? Am I likely to be life essence starved without PK'es adding to the bar? Does it drop considerably upon death? Could someone please offer some general idea of how restrictive this currency is? Thank you!
Wow, this sure does sound like a quick class question!
Life essence will naturally regen for necromancers. You shouldn't run into issues with running out unless you use a lot of your necromancy skills. There are things you can do to boost your life essence if you run low like exterminate forests etc. (Not sure if you can eat hearts still. It's been a while.). There are also artefacts you can buy or traits you can take to boost your natural regeneration.
HOWEVER : Necromancy is a governed skill. You will have to meet certain RP requirements to keep it. As a rough guide as long as you keep on the good side of Mhaldor. A Mhaldorian will have to chime in to say if non-mhaldorians are allowed to keep the skill .. instead of being an asshole to a newb.
Exterminate doesn't regen essence now, it takes essence to use (I believe just to start, even, not just on completion). Eating hearts restores a bit of essence via Cannibalism (267 lessons in, according to http://wiki.achaea.com/Necromancy). The amount of essence restored is "...modified by the experience of your victims"
Drain also exists (467 lessons in Necromancy) which will allow the transferal of essence from one Necromancer to another, though there will be some slight essence loss UNLESS you do it on Mhaldor Isle or in the city of Mhaldor (again, wiki) .
Vivisect (1565 lessons in Necromancy) seems to, though the wiki doesn't indicate if/how much- there is an artifact that boosts this, however:
A wreath of lycopod vines
It costs 250 credits.
You can also take the Truth Seeker minor trait for "bonus necromantic essence gain", though I am unsure of if it is on consume heart or it increases the passive essence regeneration.
You should be more than fine without needing to eat hearts on the regular, if you're just bashing, but once you get into pvp (especially group combat), things may start to get a little costly essence-wise, especially when exterminating.
As I recall it, you wont ever find yourself exerted for essence unless you're in prolonged raids/repeated raids where you somehow never get a chance to just pluck hearts out of corpses (enemy and ally).
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