At your birth, the doctor noticed a special organ in your body. This organ, while relatively small and not inconveniencing other organs, was unknown to the doctor. He promised your parents he'd ask around in the medical community, and he got his answer a few days later. It turns out it's extremely rare not only for the organ to be in your body, but also for it to be this well developed, as in the few prior cases the organ was reported as being much smaller. The previous people diagnosed with this extra organ had displayed impressive talents for shapeshifting even for the Clawdites, a race that was known across the Galaxy as "Changelings" due to their ability to mimic a wide range of humanoid bodies and faces.
Little did you or your parents know at the time, but the organ would give you the ability to draw additional body mass from an unknown source dimension or shunt your body mass into it for safe keeping. This in turn allows you to change into anything you can imagine, from the smallest little bug to the largest rancor. As you shift into them, you maintain your Clawdite intellect and ability to think rationally, but you also gain (from sources unknown) instincts and behavorial information of the animal species that you are impersonating. For instance, if you would shift into an acklay, you would be able to fight like an acklay would, but you would also know how to behave like a normal acklay and interact with wild acklay as if you were one of them. If a species possessed certain innate abilities, such as the vornskr's ability to hunt using the Force or the Ysalamir's ability to hide from them by blocking out the Force, you would take on that ability. All of this except for the latter you discovered during your early years, while growing up. Now, in the Clawdite equivalent of high school, you are about to discover your newest ability. Due to your far-reaching transformation skills, you've always been the target of mockery and jealousy from your peers. Today during Xenobiology (the study of off-world biological organisms), the teacher showed your class footage of the Geonosian 'brain worms', that hatched from eggs the size of your fist and had the power to invade and control bodies.
"Hmm, this is very interesting", you say, as you commit their shape to memory. The tiny organ had also given you perfect eidetic recall which you currently primarily used to remember in extreme detail what things looked like. Furthermore, it removed the pain Clawdites felt when shifting their bodies, and enabled you to maintain your form even when asleep or hurt.
Will you use this Xenobiology lesson right away, or will you experiment with it later on?