It doesn't seem to work. I don't know if it's a bug, or if the Lorica is too squishy for it to take effect. I've had it on the Lorica for several battles and I've never had it trigger. I'm wondering if the trigger is set to low as I've been below 10% health with both armor amp and shields on and died before it kicked on. I've been keeping an eye on it across a few battles and there have been at least 5 times where I would've expected it to fire and it didn't.