Is the immune replaced with a resistance to nonsilvered or just gone? The 10 point if no silvered damage probably won't make much difference than zero regen based on my experience throwing revenants with this regen below at players since almost every round involves someone dealing a negating damage type
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With silvered weapons it might be a l
ittle different if there is a very limited number of silvered weapons in the group or the AC is tuned back towards past editions where you were expected to miss more often rather than 5e's 60-80%+ hit chance expectation. If it's meant to evoke the tension we used to see with regenerating stuff like trolls even with limited access to the right damage type in past editions it needs to be
much more than 10hp or it just works out to hit it one more time if that.