I'm back with the same question as 2 years ago but for 1.16.5: #176

Just the health modifier? Because if you want to remove all difficulty effects from a mob, you can add it to the difficulty_exempt tag, it can still become a blight though, stopping that requires putting it in the blight_exempt tag

Thanks, yes I needed for every difficulty effects and blight, I will use those tags.

Wait, I just realized you meant the Entity Tag. I meant something like this: #176 (comment) since I'm using vanilla Wither Skellys