Points are valued depending on the number of survivors lost, the colour of the flashlight and perk tiers at the end of the challenge:

• Each S-tier perk = 50 points
• Each A-tier perk  = 40 points
• Each B-tier perk = 30 points
• Each C-tier perk = 20 points
• Each D-tier perk = 10 points
• Purple flashlight = 30 points
• Blue flashlight = 20 points
• Green flashlight = 10 points
• Number of survivors out of 52 still available

So for example, ending on 3 S tier perks, 1 A tier perk, a purple flashlight and 51 survivors lost = 221 points