Hidden Plasma Gun in this Level?

It is said there's a Plasma Gun hidden in Alpha Lab Sector 3, but where is it? I had visited every centimeter of this level, but still no joy of finding it. Can anyone give me a hint?--General Wild Dog (talk) 10:30, August 28, 2015 (UTC)

Changes in BFG?

I don't know if this is a change in the BFG edition or because I'm only playing on recruit, but I didn't get the secret area at the end of the red-lit hallway. If someone else can confirm this (and it's not just a one-off glitch in my game), some of the numbers on the page may need adjustment, or a note flagging that BFG has differences. {{subst:User:RobinHood70/sig}} 07:54, May 20, 2017 (UTC)