When the player character performs Melee finishers on "Terminus enemies" or "lictor", the finishing action takes a long time. Under normal circumstances, "Contested health" will remain unchanged and will eventually be fully restored. But during the "Melee finishers", if there is a "Bulwark" nearby that releases a "Chapter banner" to help restore contested health, it will cause contested health to gradually decrease. 
When the "Vanguard" performs Melee finishers on "Terminus enemies" or "lictor", the finishing action takes a long time. The "Vanguard" will be affected by perk tree "adrenaline rush" and its "contested health" will gradually decrease.