Like many series before this one, several figures were available with a foil-bordered character poster instead of a comic. Based on internet searches, there's very little evidence of them even existing, so information on them is naturally incomplete.
Figure is sometimes considered to have 'blue neck' and 'white neck' variants as well as 'black gem' and 'red gem' variants, but these are just the consequences of varied applications rather than running changes.
A Victorian-era scientist obsessed with evolution in all its forms, Nathaniel Essex allowed the immortal warlord known as Apocalypse to augment his body and strip him of his humanity. Now, he is Mr. Sinister – master manipulator and expert geneticist working to create the most powerful mutant the world has ever seen! A brilliant biologist and geneticist, Mr. Sinister is also immortal – granting him a unique perspective on human evolution. Sinister can manipulate his molecular structure, thus altering his appearance and shape. Also, he possesses superhuman strength and an accelerated healing factor.