Thread by @Herms98

Age 753 to 756: to prepare for his rematch with Piccolo, young Goku trains in that most hyperbolic of all time chambers, the Room of Spirit and Time, but he’s unable to stand its harsh environment for more than a month. He also samples Popo’s off-brand time room. #HistoryofEver

Meanwhile, down on the ground floor, kid Piccolo’s wacky adventures continue. He’ll grow into an adult over the course of the next three years, putting Dende to shame (yet he’s still a late bloomer compared to Piccolo Senior’s other children, who came out full-grown in seconds)

Now that he’s got Goku close at hand, Kami permanently removes his tail so that he can safely bring back the moon without any future monkey mayhem. But he doesn’t fully explain his true motives to Goku, so it’s not until years later that Goku finally puts two and two together.

This factoid about the moon’s restoration and the final fate of Goku’s tail is first mentioned early on in the 23rd TB, and explains why the moon is around again for Piccolo to blow up in the Saiyan arc after Roshi destroys it the first time around at the 21st TB.

Goku’s training with Kami and Popo is mostly skipped over in the manga, but the anime adds plenty of incidents. Besides traveling back in time to meet young Roshi, he tries to steal the crown of Mt. Goro-Goro, goes fishing, fights his doll clone, and generally makes zero progress

Then in the Android arc, we retroactively learn that kid Goku tried out the time chamber during this period, only to crack up after about a month inside (so 2 hours in outside time). But it’s thanks to this that Goku knows of the room and suggests using it for the androids/Cell.

We know that Toriyama submitted various ideas for anime filler, and while the time travel room isn’t specifically cited as one of these, it is suggestive that it pops up twice in filler, long before Toriyama introduced a lookout room with time-warping properties in the manga.

On the less mystical side, it’s during his training with Kami and Popo that Goku begins wearing weighted clothes, including the boots and blue undershirt that form his trademark outfit as an adult (fan artists take note: kid Goku has slipper-style shoes and no undershirt)

Not to be outdone, Yamcha and co train together at Karin Tower for awhile, then split up and train on their own until the tournament. It’s sometime during this period that Yamcha receives his distinctive facial scars, though the details remain highly classified.

On Tuesday: the marriage of heaven and hell!

Thanks as usual to @Terez27 for all the clips this week