I got my necromancer to level 96 back in the day and I think I started using this build in the 80s. Let me know what you all think and if anyone has tried this build. For optimally fast clearing, you need to run the cows around in circles to get them in tight pack, similar to how a Javazon does, so you'll want faster run/walk gear for sure. It may work OK with Bone Spirit also though. I used Bone Spear instead of Bone Spirit since it pierces and helps kill the nearest cows to the golem faster than Bone Spirit, which is single target.

cast corpse explosion several times and clear the pack.

after one or more dies, cast amp damage on the pack.

Cast Iron Maiden on pack of cows attacking your golem, wait for one or more to kill themselves on the golem and bone spear them if you want to speed it up.

Summon Iron Golem before engaging monsters.

Steps to kill large packs of cows, from what I can remember:

Didn't really matter if the golem died as long as other things had already died, since there was always new items in Cow levels to make another. The core of the build was having a very Strong Iron Golem and using that plus iron maiden to get things to kill themselves and then amp and corpse explosion.

This is my best guess! Points in Iron Maiden vs Amp damage could be adjusted according to preference.

The only problem is, I didn't screenshot my build tree, and given that it was 20 years ago I'm left wondering what the heck it was exactly. Not as fast as a Javazon, but pretty quick and self sufficient from what I can remember. I can say for sure that it was a surprisingly viable build for quickly clearing big packs in the cow levels. I don't know if anything changed since that patch to nerf how this worked, and I haven't leveled up my Necro yet. OK I have seen various guides for necros, but none of them use a build that I remember doing back in 1.09 back in the day.

Diablo 2 1.09 necromancer builds