Prevent life regen on monsters: other options besides Frost bomb?

I'm wondering: are there other options to stop life regen from monsters besides Frost bomb?

Life mastery for 50% reduction. There's also an Eater mod on helm that goes up to like 82% reduction, I think, but it only works on enemies you hit. There's also a version of that with higher % (90 maybe?) for unique/pinnacle boss presence.

Life Mastery (50% reduced) + Ryslatha minor Pantheon (50% reduced for monsters you hit recently) carried my RF through everything with life regen, including 80+iiq invitations with Cousecrated Ground + Maven heal. If you can afford Ryslatha as minor pantheon this is the best combination I found so far.

Thanks for the tips!

The helmet mod and Ryslatha both require hits, which does not work for my build.
But I had missed the life mastery option.

How nearby do I need to be for it to work?

Can monsters regeneration go negative?

I checked and players regeneration can go negative but monsters regen can not.

Or something like this:

Mark Mastery will give you monsters can not regenerate life

Essence Drain. Mine was Level 11 with no support gems and I melted them. It's not immediate so you need solid regen as well but it does the job. Kudos to braindoper on reddit for the knowledge. Combine it with Last Rites (notable which means you can annoint it - Sepia Black Black) and a curse and they go down like chumps.

Just need to exclude from the game. Or add combined mods.