If you kill any NMs during the BC, and are ejected from the BC before winning, the killed ones will respawn with 33% HP.
They will never recover more than 33% HP after a BC failure, and anything higher than that will be frozen in place for the next attempt. For example, let's say you killed Sagelord, got Forbidding to 20% and got Shadelurking to 60% before getting booted from the BC. On your next attempt (assuming nobody goes in before you) Sagelord will be alive with 33% HP, Forbidding will be at 33% HP, and Shadelurking will still be at 60%.
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