"Mutant Traps: Mutants Check In But They Don't Check Out!" (Unless by "check out" you mean "die slowly and painfully," in which case they do indeed check out!)
I was honored when Friend Computer assigned my lab, Syntelligent_Systems, the prestigious task of creating new anti-mutant booby traps for deployment across the Alpha Complex. While previous traps, such as the Room_Without_Doors, worked against one particular strain of mutant, FC demanded a trap that could ensnare mutants of all kinds. This was a challenging assignment - but I knew I was up to the task!
The question has been asked for ages: How do you build a better Mutant Death Trap? Well, we all know that mutants can be slippery. That is why I developed an extremely sticky substance to use against them. Mix two parts Acidophizz, two parts B1, and eleven parts Toothpasty_Supplement_#5 and viola: you get a substance so adhesive, it permanently gums up everything it touches (including a few dozen PLC mixing Vats that were used to produce this compound... but that's their problem, not mine).
Once I came up with this stuff, nicknamed "soopergoop", the rest of the design came together pretty quickly. The goop would be poured into a shallow pit in a dark room, mutants would step into the pit, get stuck there... and die. Eventually. The trap was simple and effective - but somewhat lacking in pizzazz. That's why I added automated laser cannons and rotating blades! It was that lethal combination of high and low tech that really "took it to the next level".
Of course, every good trap requires bait. In early field tests, we used a large blinking sign that read: "MUTANTS IN HERE HAVE HAPPY GOOD TIMES!!!" Though this approach lacked subtlety, it snared a respectable number of mutants (mostly IRs). However, the sign also attracted the attention of Troubleshooter teams that were hunting mutants. Since neither lasers nor rotating blades could distinguish between good guys and bad guys, both were puréed with equal efficiency. After careful consideration, we changed the sign so that it read "**ONLY** MUTANTS IN HERE HAVE HAPPY GOOD TIMES!!!" and started installing Mutant Traps into trouble spots throughout the Complex. Thus far, it has been a spectacular success! 2,600 liquified mutants don't lie - at least not after my Mutant Traps are through with them.
However, the project did use a great deal of Toothpasty_Supplement_#5... right around when some sectors started experiencing shortages.
Personally, I would have worded it as "PLAID CLEARANCE: UNREGISTERED MUTANTS ONLY" but then some Anti-Mutant type might well just erase the "UN" part of that... oh well.
As it happens, Tech Services has requested several additional "**ONLY** MUTANTS IN HERE HAVE HAPPY GOOD TIMES!!!" signs since the advent of the program, over and above the number of Mutant Traps actually installed. It turns out that some traitorous clones have vandalized Mutant Traps, replacing the signs with messages like "COME INSIDE FOR FREE BOUNCY BUBBLE BEVERAGE!" or "WELCOME TO BRIEFING ROOM #412/MAD".