This is Subskin Armor:

S ubskin A rmour

Thin carapace plating is inserted under the skin in various locations,

giving the user added protection against damage. While not as

impressive as most augmentations and sometimes uncomfortable,

subskin armour is very reliable. This implant adds +2 Armour

points to the Arms, Body, and Legs locations, which stacks with

any other Armour points for these locations.

Now, Bionic Replacements to locations grant:

Bionic replacement limbs are assumed to operate at the same

level of strength and dexterity as the body they are attached to—

rather than risk ripping themselves out of their host through

overpressure—though their robust construction does add 2 to the

owner’s Toughness bonus against hits scored to that particular

location.

If you have a Bionic Left Arm, you no longer have “skin” for the Subskin Armor to be under so getting +2 from that and +2 for Bionic Replacements is essentially doubling up? Yes, I know one is Armor and the other is Toughness. However b oth are "Cybernetics" and it seems like having "carapace plating" under a Bionic Arm (robust construction) is the same thing. If you put the "carapace plating" over the Bionic Arm, that is just armor like any other other (flak armor, etc.)

I have seen other mentions of this stacking being debatable.

~ alemander

The two cybernetics do not stack; there is no skin on a bionic arm to cover the subdermal armor. Studier construction of the limb suggests a Good or better version of the bionic arm, which comes with an entirely different set of benefits.

I could see an argument for allowing the armor plates to be attached to the arm structure. If your players wanted to do this, I would permit it with one condition: the extra armor plates are too bulky to be worn under other armor. If it could stack with other armor, a player could boost their durability to a ridiculous level.

The two cybernetics do not stack; there is no skin on a bionic arm to cover the subdermal armor. Studier construction of the limb suggests a Good or better version of the bionic arm, which comes with an entirely different set of benefits.

I could see an argument for allowing the armor plates to be attached to the arm structure. If your players wanted to do this, I would permit it with one condition: the extra armor plates are too bulky to be worn under other armor. If it could stack with other armor, a player could boost their durability to a ridiculous level.

i agree with this, but remember too the craftsmanship of the cibernetics replacement, a best craftsmanship bionics doesnt need to be bulky (actually this ones can give bonuses to interactions and subtlety). So if he want to stack, I personally, would rule that he would need best craftsmanship cibernetics.

The two cybernetics do not stack; there is no skin on a bionic arm to cover the subdermal armor. Studier construction of the limb suggests a Good or better version of the bionic arm, which comes with an entirely different set of benefits.

I could see an argument for allowing the armor plates to be attached to the arm structure. If your players wanted to do this, I would permit it with one condition: the extra armor plates are too bulky to be worn under other armor. If it could stack with other armor, a player could boost their durability to a ridiculous level.

I disagree with this. The subdermal armor could easily represent an armored battle ready bionic rather than a standard model. There is nothing about the quality of bionic limbs that would necessarily represent sturdier construction. Most of the benefits are more described as more efficient function and more decorative which arguably could make it less sturdy.

If you are going to limit it like that why not say armor can never be worn over bionic limbs in the first place. Imperial bionic's basic structures (barring best quality) are generally described as being very bulky so the amount added from plates thin enough to fit under the skin would be relatively minimal. Not to mention armor can be tailored and acquired at different sizes. Armor is made for everything from ogryn to ratlings so I'm pretty sure something in the right size could be found or crafted to fit over a bionic. Maybe make the armor a step harder to acquire to represent the additional tailoring required. One of the character's in my group got the biggest feral world character size so is nearly 7 feet tall. Our GM doesn't outright disallow him from ever finding usable gear that fits him right due to his size, however it is sometimes more complicated (we have to modify it, or none being the right size is the in game explanation for a failed influence test to get it for him, or its harder to acquire etc).

In general I don't think the loss of a limb should suddenly mean the character should lose the effect of an item they have or not gain the full benefit of it if they get it later.

The two cybernetics do not stack; there is no skin on a bionic arm to cover the subdermal armor. Studier construction of the limb suggests a Good or better version of the bionic arm, which comes with an entirely different set of benefits.

I could see an argument for allowing the armor plates to be attached to the arm structure. If your players wanted to do this, I would permit it with one condition: the extra armor plates are too bulky to be worn under other armor. If it could stack with other armor, a player could boost their durability to a ridiculous level.

I disagree with this. The subdermal armor could easily represent an armored battle ready bionic rather than a standard model. There is nothing about the quality of bionic limbs that would necessarily represent sturdier construction. Most of the benefits are more described as more efficient function and more decorative which arguably could make it less sturdy.

If you are going to limit it like that why not say armor can never be worn over bionic limbs in the first place. Imperial bionic's basic structures (barring best quality) are generally described as being very bulky so the amount added from plates thin enough to fit under the skin would be relatively minimal. Not to mention armor can be tailored and acquired at different sizes. Armor is made for everything from ogryn to ratlings so I'm pretty sure something in the right size could be found or crafted to fit over a bionic. Maybe make the armor a step harder to acquire to represent the additional tailoring required. One of the character's in my group got the biggest feral world character size so is nearly 7 feet tall. Our GM doesn't outright disallow him from ever finding usable gear that fits him right due to his size, however it is sometimes more complicated (we have to modify it, or none being the right size is the in game explanation for a failed influence test to get it for him, or its harder to acquire etc).

In general I don't think the loss of a limb should suddenly mean the character should lose the effect of an item they have or not gain the full benefit of it if they get it later.

Bionic limbs already increase the effective Toughness bonus of the hit location, so adding subdermal armor on top of that seems like double dipping on the protective qualities of cybernetics. You can certainly justify how a bionic limb could be reinforced to provide extra armor, but it could lead to players becoming too tanky.

Basically, just because a player can get armored bionics, doesn't mean they should get armored bionics.

One adds a Toughness bonus; one adds an Armor bonus. There is no stacking involved. The bionic limb just has extra armor. Not having skin to cover it is irrelevant.

One adds a Toughness bonus; one adds an Armor bonus. There is no stacking involved. The bionic limb just has extra armor. Not having skin to cover it is irrelevant.

I mean that both items give extra damage reduction above what would normally be possible for a character. When combined, they offer more protection than I want to allow my players. It makes balancing encounters difficult, as enemies capable of harming the super-tanky bionic-enhanced character will shred through the other players' defences.

One limb being slightly tougher makes the character "super-tanky"? Even if they get all thier limbs replaced that still leaves thier hard and torso. Torso being the thing most often hit. It should not affect encounter balance at all.

In my games, I find that people get shot in the legs way more often than should be possible My favorite incident happened when our cleric was standing face-to-face with a Redemptionist cult leader: he pulled out his combat shotgun, then promptly fired a burst into the leader's leg. He blew off the guy's foot, and the leader died screaming.

Back on topic, you could play it either way. The rules don't specifically prohibit combining the two bionics, but I disallow them for balance reasons (and because there's no skin to cover up the armor plates).

You too, Weasels? My game has an absurd amount of leg-shots. It's hilarious!

The two bionics are mutually exclusive.

If you want to have a bionic arm that gives both +2 armour and +2 toughness, sure go ahead and introduce it in your game. The existence of these two bionics does lead one to imagine a "combined product" I guess.

In my opinion the subskin armor should not stack with other armors, just like wearing a mesh armor under a carapace armor does not stack.... but that is another discussion I guess.

And why bionic arm shouldn't be covered with synthetic skin? Best quality bionic arms should allow to do that.

I would allow the stacking, but subtly would take hit, and I would also make a permanent penalty to their carry weight to represent the bulk and mass of all the bionics and armor

It's not really fair to make bionics heavier than flesh. Just remember that having bionics installed requires appropriate place where you can even start to look for them, then it takes skilled medicae specialist to install them and after 2d10 days the bionics can be used. Players should'nt be punished ano more IMO.

The way I look at it was that "synthetic skin", i.e. Fabricated Flesh from the old Lathe Worlds book (a trait of the Factors of the Lathes) was a rare and unique thing/quality. Since that was a trait of the Factors, I don't see even Best Quality Bionic Replacements having any synthetic skin/fabricated flesh. BQ to me just meant that they are not bulky, piston driven monstrosities and the like.

That is my reasoning, well one of them, for not allowing Subskin Armor and Bionic Replacement toughness to stack.

~ alemander