This section is intended to be an exact copy of what the survivor Helena Walker, the author of the dossiers, has written. There may be some discrepancies between this text and the in-game creature.
“
Species
Heterocephalus magnus
Time
Holocene
Diet
Herbivore
Temperament
Passive
Wild
Bearing a strong resemblance to its relative, the Naked Mole Rat, Heterocephalus magnus is a gentle giant that digs for plants and fungi with its imposing front teeth. While foraging, it often uncovers precious resources inadvertently, but survivors should claim them with caution, as this triggers an aggressive response.
When threatened, Heterocephalus rolls up into a ball to shield itself with the armored plates on its back, much like an armadillo. It then rolls around like an oversized bowling ball, smashing through rocks, walls, and hopefully its aggressor.
Domesticated
While hardly a ferocious war beast, Heterocephalus is an effective transport that can carry up to three passengers. In theory, it could also be siege weapon, as its rolling attack can dent even metal. Fortunately, most survivors use a special saddle that deploys a protective canopy when it starts spinning, which not only keeps them from getting squished, but provides extra protection to the rider and mount alike.
A passive creature, it does not attack unless provoked, by either attacking it or stealing any resources it has dug up after burrowing and emerging.
Wild Roll Rats regularly dig underground and pop back up in the same spot, unearthing gems. They frequently unearth Green Gems, sometimes unearth Blue Gems and rarely unearth Red Gems. Collecting the unearthed gems makes the Roll Rat hostile. They lose this ability after taming.
Appearance
The Roll Rat shares many similarities to that of a Naked Mole Rat. However, unlike a Mole Rat, it is far larger and has a armored plating covering its' back.
Color Scheme and Regions
This section displays the Roll Rat's natural colors and regions. For demonstration, the regions below are colored red over an albino Roll Rat. The colored squares shown underneath each region's description are the colors that the Roll Rat will randomly spawn with to provide an overall range of its natural color scheme. Hover your cursor over a color to display its name and ID.
This information can be used to alter the Roll Rat's regions by entering cheat SetTargetDinoColor <ColorRegion> <ColorID> in the cheat console. For instance, cheat SetTargetDinoColor 0 6 would color the Roll Rat's "body main" magenta.
Type in values of a wild creature to see on which stats it's emphasized. Green values on a high-level creature are very good for breeding. If you have already tamed your creature you can try to recover the breeding stats with an external tool.[1]
Roll Rat
The stat-calculator does not work in the mobile-view, see here for alternatives: Apps
Note that after the creature is tamed it gets bonuses on some stats depending on the taming effectiveness. This makes it hard to retrieve the levels on a tamed creature, so this tool is only for wild ones, but gives a first impression, how well the stats are distributed.
Combat
General
The Roll Rat is a generally passive creature until it is either attacked by the player or if one picks up gems that are laying nearby. When that occurs, the Roll Rat will become hostile and will attack the player. Although its damage is fairly high even at low levels, it is not an exceptionally fast creature. Put a decent amount of space between the two of you, and it will cease combat easily.
Strategy
If you are on more of a fresh character and do not have access to Large Bear Trap yet still wish to fight a Roll Rat, your best bet is to not leave its side during combat. Note that with its large turning circle, it is prone to falling off cliffs.
Weaponry
It is most preferable to utilize ranged weapons and attacks if you have the means to immobilize the Roll Rat; however, as noted above, hugging the Roll Rat's side during melee combat is your best chance at downing it. Be sure to back off quickly when it occasionally begins rolling.
Dangers
The only two ways to make a Roll Rat aggressive is to either steal the gems it unearths or to attack it directly. Otherwise, it is completely passive. As it is sometimes a source of the rare Red Gems, this provocation is often worth the risk.
Weakness
Roll Rats possess mediocre speed when not rolling, and their large turning radius oftentimes make them easy targets.
Note that the values are for optimal cases, always bring extra supplies!
For a level-dependent count of resources needed, try an external taming calculator.
The Roll Rat has a unique variation to the Passive Taming mechanic; rather than directly pressing E to feed an item to the creature, you have to wait until it burrows down into the ground. Aim at the hole and press 0 (zero) to throw the food at the hole and repeat every time it burrows back in until it is fully tamed. It only accepts Giant Bee Honey as its food source for taming.
Once tamed, however, the Roll Rat has a standard herbivore diet.
Wait for the Roll Rat to burrow. Once it's tail is up in the air, it's time to throw.
Aim at the hole and press 0 (zero) to throw the Giant Bee Honey at the hole. Note that this does NOT make you eat the honey.
Repeat all steps until tamed.
The Roll Rat occasionally begins its burrow animation but instead just unearths food - avoid being trigger happy if you have limited resources. You cannot pick thrown honey back up.
Also be aware that because of its large turning circle, it is prone to falling off cliffs midway through the taming process.
Notes
It appears as though you can "claim" a Roll Rat tame by throwing the honey on the ground in front of it. On PC, other attempts to feed it this way are ignored.
The Roll Rat's tame is cancelled if it enters combat. This completely resets ownership, progress and effectiveness.
The Roll Rat occasionally damages nearby units when it eats or emerges from its hole. This damage does not cause you to enter combat.
You have to wait until the Roll Rat starts to burrow and then throw Giant Bee Honey near them to eat.
Utility
Unlike the overwhelming majority of creatures in ARK: Survival Evolved, the Roll Rat's saddle has a durability component that is damaged by combat, or by collisions with clippable resources (except foliage) while rolling. This reduces its usefulness in combat.
Roles
Transport: Roll Rats can transport several people safely and quickly by rolling. When riding the rat and holding Rmb, , or , it rolls forward at a fast pace. On its way, it breaks rocks and trees that are in its path; however, this reduces the durability of the Saddle.
Harvester: The Roll Rat is a good Wood harvester and a decent Mushroom and Berry harvester and will even harvest berries and mushrooms by itself.
Fertilizer: As with most creatures, feed Roll Rats Stimberries and they will produce a very high amount of feces.
Bulldozer: Rolling into trees, large mushrooms and rocks will destroy them. This can be used to clear out areas of land quickly to be used for construction, although the resources from the trees and rocks are not harvested. In the same vein, Roll Rats can bulldoze their way through wood and stone structures with relative ease, making them primitive base breakers or turret removers. They do more damage the faster they're going and leveling up melee damage amplifies the damage they deal.
Travel: the Roll Rat is one of the best land travel mounts, they are faster than a Raptor, Ravager or even a Deinonychus. and more fun to travel with unlike flyers like the Pteranodon.
Raider: on PVP the roll rat can be one of the best Raiders, with their roll they Can quickly break Stone Structures and Metal Doors, also they can't be immobilized by Bola and it gives you nearly protection from Tranquilizer Darts.
Weight Reduction
The Roll Rat reduces the weight of the following resources by the listed amount while they are in its inventory:
For information pertaining specifically to the real-world Roll Rat, see the relevant Wikipedia article.
The torn dossier for this creature was first revealed on October 28, 2017.[2]
In the dossier for the Roll Rat it is shown to be a bareback ride tame however in game you need a saddle in order to ride it, this is presumably a mistake.
The Roll Rat's ability to roll resembles that of Doedicurus, however the RMB must be held down for the Roll Rat to continue rolling, and the Doedicurus's saddle does not take damage when rolling.
The dossier states that the Roll Rat's roll can dent even metal. However this is currently not the case as the roll does no damage to metal structures (but is devastating against stone structures.) Whether or not this is a bug or intentional is currently unknown at this time but as it stands, however it may be talking about its metal saddle and how it breaks over time.
Roll Rats gain more movement speed while rolling if levels into movement speed are invested and/or if they're imprinted. This can make Roll Rats the fastest creature for land travel by far but controlling them at such speeds is nigh impossible. Movespeed-invested Roll Rats would not be advised for travel on Aberration or Extinction due to the nature of the maps (Aberration has several steep cliffs and Extinction doesn't have a barrier at the map edges to stop your momentum which can lead to the death of you and your Roll Rat should you cross the edge.)
Oddly enough, Roll Rats take full damage from bullets, unlike nearly every other creature in the game.
In the Seeker dossier, it shows a group of Seekers attacking a Roll Rat.
Real Naked Mole Rats eat plants but they mostly eat the roots and bulbs of the plant. Ark's Roll Rat have adapted to eating the Giant Bee Honey.
Roll Rats are a type of Mole Rat that have some how adapted to grow a unusual size. It has also adapted to curl up into a ball and roll around giving it the name Roll Rat.
However, Helena's claim that Roll Rats exibit this behavior is contradicted by the fact that wild Roll Rats in-game have never been seen to roll up in a ball and can only do so when tamed and eqipped with a saddle. On the contrary, Wild Roll Rats can dig but as soon as they are tamed, they lose this ability.
Helena mentions in her notes about wild Roll Rat's eating plants and fungi. While they do when tamed, they can only be tamed by giving it Giant Bee Honey first.
Mole Rats in real life have a eusocial structure similar to, bees, ants, termites and wasps. The Naked Mole Rats are lead by a queen and are the only mammals with this behavior, however Ark's Roll Rat does not have this behavior or is at least never shown similarly to the Titanomyrma . The Giant Bee and Reaper species however do show it.
While taming it is also possible to throw the Giant Bee Honey while being riding on a tame e.g. Argentavis. It is not necessary to stand next to the hole. This makes taming easier and safer.
They are future relative of the Mole Rat that had to adapt to the changes of the environment in Aberration after the Ark became damaged.
Like many passive tames the Roll Rat can be knocked out in game, they cannot be tamed once they are knocked out.
No
Yes
Region 0:
Region 4:
Region 5:
Health
Stamina
Oxygen
Food
Weight
Melee Damage
Movement Speed
Torpidity
Level 1
Giant Bee Honey
Giant Bee Honey as its food source for taming.
, or 
, it rolls forward at a fast pace. On its way, it breaks rocks and trees that are in its path; however, this reduces the durability of the 
Saddle.
Wood harvester and a decent Mushroom and Berry harvester and will even harvest berries and mushrooms by itself.
Fungal Wood.
Stimberries and they will produce a very high amount of feces.
Raptor, 
Ravager or even a 
Deinonychus. and more fun to travel with unlike flyers like the 
Pteranodon.
Stone Structures and 
Metal Doors, also they can't be immobilized by 
Bola and it gives you nearly protection from 
Tranquilizer Darts.
Fungal Wood
Wood
Thatch
Berries
Doedicurus, however the RMB must be held down for the Roll Rat to continue rolling, and the Doedicurus's saddle does not take damage when rolling.
Titanomyrma . The 
Giant Bee and 
Reaper species however do show it.
ARK: Survival Evolved Changes
Roll Rat is added to the game
Weight reduction on 
Stone, and instead now has a 80% 
