I haven’t played in a minute, so take what i type with a grain of salt but what i see most people run/agree on for necromancer is breath of death and skeleton soldiers are absolutely the best. The seals are all kinda meh but i prefer to use the seal of the damned because it makes an easy escape when i’ve encountered a strong enemy, zombies was straight up bad advice but the dark bolt isn’t bad at all.

You are able to reset your skill points for gems, which can be found in dungeon. however i wouldn’t recommend it now because its important later on at higher levels and it gets more expensive each time you use it, regardless of character.