Doesn't stack. Use the higher value.
While that isn't necessarily a bad ruling, I don't think it touched upon in the rules. Generally speaking, racial armor and worn armor stacks.
Assuming that this situation is possible (more on that later), previous experience tells me that the armor should stack. However, I do agree that it might be a bit unbalanced to be able to stack up Hardened Armor like that. One of my friends suggested a sort of compromise, the two hardened armors stack for the purposes of dice pool and bonus automatic hits, but only use the higher value for checking for immunity.
I am trying to figure out how the critter power Hardened Armor would stack with other Hardened Armor. I have a Drake in a game I run and he's saveing up to buy a suit of gently used Mil Spec light armor. So does his 5 points of hardened Armor stack with the Mil Spec or what?
Now, on to the plausibility of this situation. Make sure you take into account that getting second-hand milspec armor is already a difficult situation. It is Custom Fit to the user and extremely sensitive to exact body specifications. Changes in attributes mean that the armor doesn't fit anymore. So, how exactly is this Drake getting in (and staying in) his Milspec armor while changing forms?
