Got a barbarian I'm looking to use for farming a sunder, even if it takes three years. he's whirlwind right now for the general pvm experience.

heralds cause issues. especially with thorns. generally tough to sustain given their damage without using a belt full of rejuvenations. I've used other characters (lock/hdin) to take them down with ease.

anyone playing with any barb strategies to take these things down without as much of a struggle?

Berserk is viable vs thorns, but you wont leech then and ur defense will be 0.

I tried a frenzy barb according to the guide linked here: https://www.reddit.com/r/Diablo/comments/ffixoa/guide_the_100_gameclearing_frenzy_barb_d2/

I quickly created it in single player to test it and it all went very well, on players 8, well... until I met a Herald in the tombs with loads of skeletons. Can't leech and they constantly respawn, that also kills the merc. I stopped right there, but maybe there's a way to overcome this (teleport?), as other than that, this build was more than fine.

Especially the advice to just hold down right click (= frenzy button) and the barb will automatically attack anything in his way was nice. No permanent clicking needed.

Throw/ww hybrid, or even pure throw is what you need.

Throw is the best build for density destroying.
WW is better dps vs single targets, but heralds are surrounded by mobs anyway.
You could clear the pack with throw then finish the job with WW for a bit faster kill than just using throw.
But throw ignores the dmg returned if its problematic.

very much enjoyed sins meta brawler, prob my fav barb build. maybe too many skill points required for herald hunting.

with heralds though, I think zerker is the way. WW got wrecked by thorns but I horked fire sunder off t1 fright herald with zerker build.