Might and Amp damage makes skellies good enough. Insight merc makes infinite bone spears and ce good enough to chain down groups. My d2r online necro following this build is level 70ish and almost done hell, easy peasy. Clay golem scales with enemy strength because of slow on hit, making it the best golem. Then you can get your 1 point revive and decrepify before maxing bone spirit for synergy. 1 bone armour, 1 Amp damage 1 ce, 1 teeth. 1 point clay golem, 1 golem mastery, I summon resist. Merc good with might and insight, probably want life steal from helm or armour. Look for resist gloves, frw resist boots and life/resist belt.Teleport staff on switch is a must for all non-sorc characters imo, best to shop act 3 normal when you are level 23.

Gamble rings and amulets for fcr/resist/skills on ammy. Rhyme or splendor shields (shrunken heads with bone spear/ skel/skel mastery best) until you can make a spirit shield(monarch). White runeword wand is great, I spent an hour shopping in act 2 for a +3 bone spear +2 summon skelly base, which is great through hell.

Make stealth/smoke runeword armour until you find skin of the vipermagi or better armour. Its best to use a build that is self sufficient for getting through the rough until you can completely deck put your character to make those godly builds work for you. Some builds only work with the right gear and until you have that it is not ideal for soloing through hell.

Or LF/CS and then have a bow on switch and put points into explosive arrow or frozen arrow. Id recommend you respec to max out psn jav/plague jav, then max LF/CS and then leftover points into passive skills (definitely pierce and at least 1 in valk). If you're trying to solo through hell, and you don't have other people to play with to fill in your weaknesses as a single damage type build, or you don't have the best gear to account for the same issue, you really want to try a different approach. Meaning you have decent gear and idealy infinity. Pure lightning jav is a build intended for being fully geared. If you're playing solo (i play on single player rn until ladder starts) id recommend not being pure lightning jav.

Diablo 2 summon necro hell unleashed