This is the latest in a series (of indefinite length and regularity) of blog posts memorializing cancelled toys. Our figure today is Hasbro's Croil.
Part of the planned second series of the Visionaries line, Croil (a combination of "cruel" and "coil") was cancelled along with all the rest of his fellows. It was late in the process, though, as evidenced by that Neal Adams turnaround for the figure then known only as the "Cybro-Serpent." The art for his planned chest hologram was done:
And even reached the sculpt stage (by Bill Merklein):
And he even appeared in the 1988 Toy Fair catalog, which shows us his planned colors:
His shield, fittingly, has a snake motif. Production notes from the time identify the two images for his shield as "baby snake" and "cobra," so maybe he would have had some kind of time-control powers? Aging and de-aging things as his means of fighting/destroying? Only the toymakers of four decades ago could say.
That line probably would have done better if they could have made the holograms small enough to have the figures be compatible with G.I. Joe. Being slightly larger meant they couldn't ride in the vehicles, and so an entire play pattern was lost.