Test Muscle!
Here is the almighty Test M.U.S.C.L.E. (#169)! As a kid, I used to put him through all kinds of tests, stunts, and evil little tortures. I was interested to see just how much abuse a M.U.S.C.L.E. could take until it was completely destroyed! As you can see, he's still in one piece! On the image above, you'll see the results of some of the tests labelled.
Why was I hell-bent on destroying this poor little fellow? Well, I always thought that he looked like a urinal! Needless to say, he was my least favorite M.U.S.C.L.E., so I deemed him Test M.U.S.C.L.E. and the rest is history!