(Aug 29: Since TFT Patch 9.17, the Burn Effect (Grievous Wounds) applied by Morello doesn’t fully prevent healing, instead it reduces it by 80%.
Aug 14: This article has been updated to reflect the Morello and Red Buff changes in TFT Patch 9.16).
July 31: This article has been updated to reflect the Nobles Bonus update in TFT Patch 9.15, but the effects’ interaction hasn’t changed)
When you’re dealing with tanky champions that have any kind of Health Regen, your two options to counter this is to use Red Buff or Morellonomicon, because they prevent healing.
The question is, do Red Buff or Morello prevent/disable healing granted by the Noble’s Bonus?