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From the Scientific Journals of Twilight Sparkle (#47 Liquid Thaumaturgy)
 
Experiment 8
 
Entry #1: Though it is both dangerous, and completely insane, to experiment on oneself, I feel it is both prudent, and necessary, given the exact nature of the … enhancements I wish to incur with this potion. Luckily, the book on potions that my counterpoint, Princess Twilight Sparkle, lent to me has proven most insightful on the specific topics I am studying.
 
Entry #2: The first potion is a mild success. Musculature and muscle definition has increased significantly, bringing me up to strength levels enjoyed by my friends Applejack (without her magic geode) and Rainbow Dash. Mammary enhancement was also significant, bringing me from an A-cup to a modest D-cup. Unfortunately, the potions effects wore off 20 minutes, 19.00005 seconds later. Luckily I had just finished testing my new build on my brother’s old weight set and did not injure myself. Must investigate further on increasing the length of the enhancements, hopefully permanently.
 
Entry #9: I have taken a week off from this experiment after the last potion made me violently ill. Luckily, I was able to convince my parents (and friends) that it was just food poisoning. The results of this test have been much more fruitful. The duration of the enhancement has increased to 69 minutes, 38.32952 seconds. The strength increase was approximately double previous tests, bringing me up to around the level of my brother or Big Macintosh. The growth of my bosom was actually larger, with my size becoming a frankly rather large I-cup - not quite as large as Fluttershy’s, but very close. I also noted an increase in my height of approximately 8 inches. Further experimentation is needed to determine if this is a side effect of the stabilizing agent, a result of increasing the amount of enhancing magic in the potion, or a combination of the two.
 
Entry #15: After visiting Equestria again, I have returned with a new book on potions - one Dr. Legwarmers’ Guide to Physical Intensification through Magic and Potions. Bizarrely, Princess Twilight almost seemed to have the book ready for me…
 
Entry #16: This latest potion seems to have been a complete success. The growth was much quicker than before, taking only 58.23 seconds to reach maximum size when the previous formulation had taken 2 minutes 16.6 seconds. Muscle and strength enhancement is nearly immeasurable given current technologies - I was able to move several pieces of lab equipment (the lightest of which was approximately 3 tons) single-handedly and barely felt the weight. Likewise my breast enlargement is similarly off the scales, but only because I don’t believe there is a long enough measuring tape in existence. I couldn’t even do some rough mental calculations given how little of my body I could see. My height has also approximately doubled, but this is a rough estimate based on landmarks, my changed perspective, and some quick head algebra. It has also been exactly 4 hours since I took the potion and I do not feel any signs of it wearing off as of yet, while the longest any of my other potions had lasted was 127 minutes and 48.79678 seconds. More data will be needed to see how permanent these effects are.
 
Shame about my poor lab coat though.
 
 
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Another wonderful commission from the lovely AutumnMelody
 
Once again, the story is by me.