Multiplas sneak critical and regular criticals seems to do a ridiculous amount of damage. I can only guess its a bug. I can one shot sneak attack kill deathclaws with it, yet I cant even do that with the YCS gauss unique(supposedl the hardest hitting weapon in the game with MC ammo).
YCS and I'd guess gauss rifles too, are screwed up and in VATS they do not get the proper bonuses when performing a sneak attack. A sneak attack head shot with Mc ammo should easilly kill a deathclaw, instead it only does 2 bars.
The laser splitter mod is completely worthless. It makes the rifle you put it on a completely useless piece of trash.

Look at ammo usage of that thing.

The Multiplas dealing so much crit damage isn't a bug. It does 105 crit damage and shoots three projectiles. Critical damage isn't split between projectiles, so its doing an extra 105 crit + 35 base per projectile(420 damage in total if you crit... and a sneak attack multiplies critical damage by 4).
And the laser splitter is used for a very specific purpose... the purpose of sneak attacks. Theres a reason why one of its other mods is a scope.

Ah so thats why the beam splitter works that way...

Wrong. Multiplas does the correct damage in VATS mode. it only does the ridiculous damage outside of VATS mode. Go test it some.

/facepalm
I just tested it. The question is, why didn't you test it? A deathclaw takes 328 critical damage when all 3 projectiles hit outside of VATs on Normal difficulty. No other modifiers were used. Deathclaws have 30 DT, so 328 damage is close enough to the projected 330 damage.

The bug is VATs, but VATs has been bugged since FO3.

How are you getting the exact numbers on these things? Given the Gaus rifles being completely screwed up for VATS sneak attack, this wouldn't surprise me much. In either case, it's bugged in VATS or outside of VATS. It's bugged nonetheless. Oh, and your math is terrible. 90DT, not 30. You have to multiply it by 3.

I did multuply it by 3. Multiplas does 420 damage on a crit. 90 DT turns it into 330. Are you just arguing for the sake of arguing?

You didn't answer my question. I didn't pay much attention to your numbers cause you have not said how you are getting them. Further, you said sneak attack multplies the crit by 4, which is simply wrong. Crit doubles the total damage of a nomrla crit. 150 base + 50 crit, would sneak attack for 400 damage, not 350.

From Living Anatomy, how else?

Cause I don't trust it. I have max damage 162 YCS, and sneak attack with improved ciritcals. That should do 534 damage, 504 after DT. But the deathclaw is left with 70 hit points.

I think the problem is you're expecting damage calculations to behave a certain way, but when the game shows you different results, you stick to believing in your calculations instead of changing it around.
For example, (1.5*210) - 30 is going to get different results compared to 1.5*(210 - 30)

To drive the point further, I just tested the YCS without any multipliers. It did 178 damage on a crit against a deathclaw. Thats close enough to the expected 180 damage. The only thing strange is why theres a 2 damage difference between estimated and actual damage with both a multi-projectile weapon and a single projectile weapon.

Are you trying to say it's an order of operations issue? Huh? What do you think the formula is? You certainly did not apply it to the previous multiplas scenario.

Its not just an order of operations issue. Multipliers could be additive with other multipliers, they could also be multiplied. Heck, depending on how its coded, multiplier A might be additive with multiplier B, but multiplied with multiplier C.
I have no idea what the formula is when you factor in multipliers. I don't care enough to run tests.
And I did apply a formula to the previous multiplas scenario:






You're obviously arguing for the sake of arguing.

dont forget on a crit there is no damage threashold.

This is simply incorrect. Try using some hollowpoints with a sniper gun and 100% crit rate and you will see very quickly that is not true.

It's not exactly, bugged, but it's a shotgun style weapon, and therefore acts like every shotgun weapon in the game. Basically, outside of VATS when it crits, every single projectile gets a crit multiplier, while in VATS, you only get a 1x crit multiplier. Hence it's better not to use VATS while sneak attacking with shotguns.

It's not a bug, it's a feature!

I thought they changed the shotgun mechanics... Like why shotguns do 100% more damage in VATS than outside of it. But who knows. This would make sense, though, and I guess it's not too overpowered since it's so hard to hit with all three plasma balls.