The classic Megatron is a giant robot who turns into a pistol the size of a human hand. Where does all that mass come from, and where does it go? Fans on Reddit have asked for decades.
The real-world answer
Megatron's 1984 toy was a transforming pistol, and the cartoon had to match it. Animators simply drew him at whatever scale suited the scene: a giant one moment, a weapon in Starscream's hand the next. Similar inconsistency applies to Soundwave the tape deck and his cassettes.
The in-universe answer
Later, fans and writers coined the term mass shifting — a hand-wave technology letting Transformers move part of their mass into another dimension during transformation. It's rarely explained in detail officially, but the idea stuck.
How modern versions dealt with it
Later series and films mostly avoid such transformations: Megatron became a jet, a tank or a truck, roughly his own size. But the classic 'tiny' transformations still live on in toys and fans' nostalgic jokes.
