Some comic book villains are inseparable from the heroes they antagonize, which allows them to pop back up every time their nemesis gets rebooted. Others are less well-respected and subsequently never get the faithful adaptation they deserve; Aleksei Sytsevich AKA Rhino is tragically in the latter camp.
Rhino was created by Stan Lee and John Romita Sr. in The Amazing Spider-Man #41. Introduced in 1966, Rhino entered Spider-Man's iconic rogues gallery before luminaries like the Shocker and Kingpin, both of whom have found homes in the Marvel Cinematic Universe.
The Rhino is one of Spider-Man's most prevalent villains, and also probably his least intelligent. Aleksei Sytsevich is a Russian mafia thug who willingly decides to undergo a series of chemical alterations that cover his body in a nearly impenetrable leathery hide. This process also makes Sytsevich immensely physically strong and arms him with a pair of large razor-sharp horns, though he occasionally gets his powers from different means.
Almost immediately, Rhino used his newfound strength to violently rebel against the Soviet agents who empowered him and begin working as a supervillain for hire. Though originally created for and almost always pitted against Spider-Man, Rhino has also tangled with other heroes like The Hulk, Doctor Strange, and The Punisher. Rhino is often the muscle for a larger team, he's a regular member of the Sinister Six, among other villain teams. Rhino dies or is rendered comatose numerous times throughout the comics, but always seems to return. Forty-eight years into the character's presence, he got his first big-screen appearance.
The Amazing Spider-Man 2 was an intensely controversial film, earning criticism from a variety of angles. The character was portrayed by veteran character actor Paul Giamatti, but the performance is wasted on the role. The Rhino is barely present in the film, he appears early on as a tattooed Eastern European thug who is foiled by Spider-Man, then returns in a rhino-themed mech suit moments before the end credits. The film makes Rhino's powers mechanical, rather than chemical, which is not unheard of in the comics, but does look ridiculous.
The suit was clearly well designed and is based on a good idea. It is meant to look as if it was assembled from old Soviet-era parts, because that's what a Russian mob enforcer could afford. Unfortunately, in its brief appearance, the camera captures it from a great distance, set against very real-looking New York City streets. It looks like a toy, and Giamatti's tiny head sticking out of the cockpit looks like it was designed to be silly. Rhino was almost in more trailer footage than he was in the actual film.
The Sinister Six is clearly teased throughout the Amazing Spider-Man films, and Rhino was clearly meant to be a part of that, as he was in the comics. Unfortunately, or fortunately, depending on your perspective, the franchise was canceled after its second entry, to be replaced with the ongoing MCU Spider-Man series. A wide cross-section of Spidey's rogues gallery has been adapted into the Marvel empire, now including several iterations of villains from previous films, but that look back did not catch Giamatti's Rhino. The Rhino has appeared in various cartoons and video games, but with the cancellation of the Amazing series and his exclusion from the MCU, his film screentime is still limited to around fifteen minutes.
The Rhino is rarely a complex character; typically he likes money and dislikes Spider-Man with little room for further depth. His simplicity, however, could be an asset in the realm of superhero villains. Marvel gets plenty of hate for their villains, typically either for being generic or poorly developed. Marvel has responded by developing some of their villains to greater depth than that of their heroes, but sometimes, a straightforward musclebound monster is fun to have around.
A more classic take on the Rhino, massive with grey leathery skin and horns, could pull off a much more imposing and scary villain performance. The Rhino should be more than a physical threat; he should be an unstoppable force that Peter Parker struggles to contain. Since Rhino is often part of a team, introducing him as a force multiplier while Spidey tangles with a more fully developed villain is also a fun idea.
The Rhino is a villain that could work in a variety of roles, but his one disastrous appearance in cinema has given him a bad name. The Rhino is a dumb man in a world of geniuses who willingly subjects himself to unethical chemistry to gain the raw power to face his foes. Most Spider-Man heroes and villains got where they are through super-science, Rhino got there as a willing beneficiary of someone else's work. Peter Parker got great power and took it upon himself to invent the tools to use it with great responsibility. Aleksei Sytsevich demanded power and exclusively uses it for his own gain. Even a musclebound thug dressed like the last horned megafauna can be a clever villain under the right creator.