As far as I know, they're in the data but don't drop. If this is the case, then we need to add them as a drop to some mobs. Could you make a post under "Feedback" suggesting that we add Gun Production Stimulators as a drop? This way, it'll be there as a reminder for us. Thanks!
Matt said he'll add it in the next SC. Yet 5-2 SCs passed by and I don't think he added it. I don't mind waiting though...
