Rancors have been present in the Star Wars universe for almost the entirety of the franchise's long history, first appearing in Return of the Jedi (1983). Rancors have seen their lore revitalized in recent years, with appearances in The Clone Wars, The Bad Batch, and The Book of Boba Fett propelling them into the mainstream.
Star Wars fans that aren't familiar with the Rancor appearances in books and comics may not know certain facts about the iconic species. The Rancors aren't simply unreasonable monsters, but a species of beasts that can be tamed and have their own cultures amongst their own people. When they do attack, however, only Jedi with the strongest Force abilities can deal with them.
6 Their Homeworld Is Dathomir
Dathomir has been portrayed as being home to many dangerous and scary-looking beasts, perhaps to reflect the Dark Side energy that congregates there. While a Rancor hasn't been seen on Dathomir in live-action nor animation, the Star Wars Character Encyclopedia confirms that the world is home to the species.
Since the Zabraks have to share the planet with Rancors, inevitably the latter would be tamed by the Night Brothers and other inhabitants. With that in mind, it's no surprise Darth Maul was such a fearsome warrior. In fact, Star Wars fans may have seen him fighting a Rancor in the canceled Darth Maul game. Unfortunately, the world will now never know.
5 Rancors Are Found On Multiple Planets
The Rancors aren't just featured on Dathomir and Tatooine (Return of the Jedi, The Book of Boba Fett), but they are actually present on multiple planets across the galaxy. Rancors can also be discovered on Felucia, as seen in The Clone Wars episode "Bounty Hunters". They can also be found on the planet Vodran, as confirmed by the canon junior novel Join the Resistance. Finally, Rancors are present on Teth (Star Wars Databank).
Having it established that Rancors can be found on multiple planets across the galaxy, it's interesting to think about how they could show up in future Star Wars projects, maybe as a surprise cameo appearance while a character explores a new planet. Just because The Book of Boba Fett features a tamed Rancor, doesn't mean Ahsoka can't one day run into a Rancor that she has to defeat, for example.
4 There Are Multiple Subspecies Of Rancors
Fans who haven't delved into Star Wars' Expanded Universe so much may not know that there are subspecies of Rancors. Jungle Rancors can be found on both Felucia and Teth (The Clone Wars, Star Wars Databank), and these are also known as Hunter Rancors due to their greater speed and sense of smell compared to other sub-species. These were meant to feature in The Clone Wars' animated pilot movie, but the scene was ultimately deleted. This is a shame since the Rancor storyline was one of the best Clone Wars arcs.
There are also Rage Rancors, which appeared in Star Wars: Commander, a mobile strategy game released in 2014 and shut down in 2020. These had greater strength and toughness and hardened shells compared to other sub-species. They were extremely hostile and more destructive than other Rancors, which already set the bar high based on The Book of Boba Fett Season 1 finale.
Finally, there are Shadow Rancors, which also appeared in Star Wars: Commander. These were called so because of their black-tinted skin and more muted back horns than the other Rancor sub-species. They were still extremely aggressive, attacking anything within arm's reach.
It's fun to think about different types of Rancor species that could show up in future Star Wars live-action projects.
3 Rancors Are Reptilian
Rancors were designed for Return of the Jedi as a cross between a bear and a potato, designed for an actor in a suit in mind. In the end, Lucasfilm decided to go for a rod-operated puppet, and from 2004 onwards, Rancors have been rendered digitally both for the Original Trilogy and subsequent live-action and animation appearances. Fans will know that Jar Jar Binks, a controversial character, was also rendered digitally, as was Yoda after previously being a rod-operated puppet.
It's cool to think that aliens have similarities to the creatures found on Earth. It helps fans relate to the characters and their situations while allowing them to better draw comparisons.
2 Rancors Follow A Social Hierarchy
Like many species found on Earth, Rancors respond and follow a social hierarchy, where there is an alpha Rancor who remains so until he is defeated by another member of the species. These types of hierarchies are normally found in species with pack mentalities, which Rancors also possess. It's funny how even Star Wars bounty hunters and other sentient characters can have so much in common with beast-like creatures.
This pack mentality contributes to why Rancors are so loving towards their owners, as shown in The Book of Boba Fett. It also plays into how the Witches of Dathomir were able to domesticate them, as outlined in various books and comics from the Expanded Universe.
1 They Get Their Teeth Cleaned By Birds
It is a gross fact that apex predators such as Rancors will get disgusting teeth after butchering and eating lesser creatures. This isn't just restricted to Star Wars, with many iconic old PlayStation games featuring massive beasts. On their native planets such as Dathomir and Felucia, their dirty teeth will be cleaned by birds after they've hunted and killed for the day.
It's unlikely that this practice improves the breath of a Rancor, but it's interesting to think of these two species having a cordial relationship to the point of the beasts allowing these birds to go into their mouth and clean their teeth without killing them.