After more than 25 years of the Transformers franchise, it's really no surprise that many Transformers released today are homages to Transformers of earlier years. Even granting this fact, some homages are more surprising than others. It sometimes seems like the official channels don't know that the original Transformers line kept putting out new characters after 1984 and 1985. The original Overkill was released in 1987, appeared for all of two seconds in the original cartoon, and faded into obscurity for the next 20 years.
The original Overkill (seen here on the right, sadly without the missile batteries he originally came with) was paired with fellow dinosaur Decepticon Slugfest, who had just as much (?) screen time as Overkill. Although Slugfest's original toy was reissued before Overkill (in 2009. Actually, Overkill's original toy has still never been reissued), only Overkill has been homaged with a new toy (seen here on the left), a repaint of Classics Grimlock.
Although both Overkills are most notable for their Tyrannosaurus rex modes, their alternate modes couldn't be more different. The original Overkill transforms into a cassette, whereas the new Overkill transforms into a robot. The idea to use such an utterly dissimilar toy as Grimlock to be Overkill may seem a bit odd, but this is actually an idea that fans came up with before Hasbro. At BotCon 2007, customizer Shawn Tessmann, who runs the annual customizing class, chose to use Classics Grimlock as the basis for a new version of Overkill. The idea was very popular, and Hasbro did a similar (but official!) version of the same concept just a year later. Unfortunately for most US fans, Hasbro's Overkill was not originally released in stores, but was a "Special Edition" exclusive to Hasbro's online webstore. The branch of Hasbro in Asia and Australia apparently commissioned the toy (along with new versions of Optimus Prime, Megatron, and Drag Strip), and HasbroToyShop.com took advantage of the production. After a few months, a few fans reported seeing some of these "Special Edition" figures at discount department stores like Marshall's, and for considerably cheaper than HTS's $15 asking price. Unfortunately, these sightings were rather scarce, and so not a reliable source for most fans.