I am running a one off Gamma World adventure and am looking for some help/advice on fleshing out the adventure. I have most of the encounters basics down but looking for advice on them and one more encounter.

The basic idea is they are rats in a Scientist experiment. I am looking for good Science Fiction tropes to use and another experiment or 2 to run them through.

What I have so far:

Mice in the Maze: I am thinking of a skill challenge of a maze. Using skills such as Perception to smell the cheese at the end of the maze and to notice the walls shift. Mechanics to stop the walls from shifting or opening walls. I am not sure if I want a combat challenge in here or not. I.E. Having traps. I might just use the traps for failed skill checks.

The Monologue/Send in the clones: I am thing the last "Boss" fight I am thinking of running as "2 encounters" They get into the final lab and see the boss that has been studying them. He calls in clones of the adventures, only they are the evil opposite clones with the evil goatees. I have everyones origins and I am going to revers them. I.E. The Rat swarm/Speeder will be a Speeder/Rat swarm. Which will not really effect the powers much but I will have them look slightly different. THe above PC is made up of many smaller rats but is very tall and thin still. While his clone will have fewer long thing rats and so on.

Once they defeat the clones I figure the Scientist will go into a 5 min monologue while the PC get their short rest. They the force field keeping them apart will break down and they will get to finish him off or if the part looks to warn out or ready to go they can escape leaving it open for future one off between our main game.

SO I need at least 1 more maybe 2, good encounters. AS well as some good scifi troupes to use. I plan the Scientist studying them to be the White mice from Hitchhikers Guide to the Galaxy. I am going to have Hamster trails running thought out the roots that they may notice the mouse or mice in. I am thinking of using the Personality doors as well. ALso there is the Evil clone thing. So any other ideas and advice would be great.

Any creature ideas and base creatures to convert over would not be unwelcome. I pplan on using the adventure tools and look throught to find some creatures I like as base and just re-fluff them to what I need. But starting ideas would not go wrong. Thanks in advance.