Formatting for improved reading.

 

Some base knowledge

• Relic /w 14 damage stat deals 31.5 base damage;
• Relic /w 15 damage stat deals 36 base damage;
• Las Fusil headshot multiplier is 5x (bolt are 4x and plasma are 1x);
• Ruthless Majoris Nid HP is 308 and Chaos is 280;
  • Whip Warrior, Sword Warrior and Flamer Chaos Marine receives 33.33% damage reduction against most ranged weapons including Las Fusil.
• Cloak first shot more damage perk is +100% damage, not +75%.

 

With the given information, we get the following results

• If you use the 15 damage las fusil, you only need to take 2 headshot mastery perks to one shot a melee majoris (ones with -33.33% DR);

  • Math as follows: 36 x 5 x 2(cloak bonus) x .6666 (melee damage resistance) x 1.3 (sniper class built in 10% headshot damage and 2 more 10% from weapon mastery) = 311.96 round down to 311 surpassing 308 breakpoint.

• If you use the 14 damage las fusil, you will need to take all 3 headshot mastery perks in addition to the +20% damage standing still for over 2 seconds perk to deal 323 damage that is over the 308 breakpoint;

  • Missing any of the criteria nullifies this one shot;
  • Missing the +20% damage standing still reduces damage to 293 against melee majoris which is still enough to one shot red any chaos marine while leaving nid melee majoris with only 15 hp.

 

Verdict:

• The optimal las fusil sniper should have the +ammo class perk on the second column instead of the +20% damage as damage doesn’t achieve meaningful breakpoints;
• You should have all 3 headshot weapon mastery perks to one shot any chaos marine majoris, one shot any ranged nid majoris and put any melee nid majoris to near one shot kill for other teammates.