Flash was easy enough to work in that many companies would produce Flash applets, even games, merely as promotional content, intended to be cheap and quick to make and ultimately disposable. Many of these games were lost when the websites they were a part of were taken down.
The Flashpoint Archive project, headed (I think) by BlueMaxima, has as its mission the preservation of these ephemeral creations. A post on Flashpoint will be coming eventually, but in the meantime I’d like to point out a 2021 Youtube video by (adjusts glasses) “Goober13md,” although I suspect that he may not actually be a medical doctor.
Goober13md’s beat is all things Monkey Ball. He made a video about the search for, and ultimate rediscovery, of three Flash games commissioned by Sega to promote the first Super Monkey Ball titles, as well as one for Super Monkey Ball Adventure (which Goober13md is understandably reluctant to mention by name). It’s an informative story about the difficulty of content preservation in a time, which is still ongoing might I add, where companies don’t see their web presences as anything more than transitory. Look look, see see!
The Super Monkey Ball Flash Games That Were Lost For Over a Decade (Youtube, 29 minutes)