Just looking at it I think for my team Velk's Ama would need 787 min RCV for my Viper run to work out. I have 7,862 hp, which means I need a minimum of 3,931 healing per round to recover >=50% for Perseverance. ROUNDUP(3931/5,0) = 787?
Starting at about Round 28 you can be 1 shot by an Ogre +...