|Weight||From 40 lbs up to the full weight of a mountain|
|First mentioned||Will of the Empress|
|First appeared||Battle Magic|
|Latest appearance||Melting Stones|
Luvo is first mentioned in Will of the Empress, although the mention gave readers little details about his appearance or nature. He is a heart of a mountain that is located in Yanjing, though he decided to join Evvy in her journeys. The meeting may be written about in the unreleased book that focuses on the Yanjing war, however Melting Stones describes the matter in passing, and that Luvo's mountain still stands despite his being away from it. As of Melting Stones it had been two years since Luvo first came to the above-ground world.
Luvo is described by Evvy as being about eighteen inches tall, and shaped as a bear. His entire body is made of clear, deep green and purple crystal that looks as though it has been smoothed by water. His face is a point, not a muzzle. It has been established that although he looks like a rock he is not truly a rock, and this is reflected in his ability to walk, talk, and move his head-knob (sometimes referred to as a head-lump). Jayat also remarks on how Luvo 'made' a mouth, so it is assumed that Luvo only has a mouth when he makes one to speak.
Luvo is able to adjust his weight. This is generally dictated by how much he likes the person, and whether the person is a stone mage. For example: Jayatin finds carrying Luvo to be strenuous despite Luvo's like of him, because Jayatin does not have the stone magic that Evvy has. Changing his weight has no affect on Luvo's size, which remains eighteen inches tall (small enough to fit into a sling on Evvy's back). Evvy theorises that others believe that Luvo would weigh 4 to 5 pounds at most, because of his size, before they pick him up and find otherwise. For those whom he likes, Luvo can adjust his weight to an estimated 40 points, although Evvy's stone magic allows her to carry him as though he were lighter.
Without a physical need for food, Luvo dines on the power of the earth. He does not drink, but enjoys being doused in water at times. He has said that he was born in a volcano a very long time ago, but cannot go back to one because of the extreme heat.
Possibly Luvo's most prevalent trait is that he is a very patient being. Luvo is wise and not likely to protest to offensive comments made by people who make assumptions about him. His only reaction to any of the remarks made in Melting Stones was to inform Headwoman Azaze that he preferred to be called Luvo rather than 'talking rock', as "talking rock is unflattering at best". Evvy often reflects that if she or Rosethorn did not correct people's wrongful assumptions about Luvo, the assumptions would never be corrected because Luvo would never correct people himself. This reflects Luvo's relatively easygoing nature, which lends itself to him being very diplomatic.
Evvy finds Luvo to be a good friend and companion for her as she travels, and indeed he seems to offer her much guidance and companionship throughout Melting Stones, and left his mountain in Yanjing to travel with her. Luvo does not tire of questions, and likes to share his knowledge with others. He is highly protective of Evvy, leading him to become unsettled and afraid when he believes her to be in trouble. The events in Melting Stones]made him anxious, while Evvy and Rosethorn acknowledge that he "had faced armies in Gyonxye without even grinding his crystal jaws". Luvo does not believe humans to be entirely good creatures, as within two years he had see both the best and worst of mankind. Despite not suffering the same emotional and physical pain as Evvy, Luvo is very sensitive to the girl's reaction to the war and does not tell others of the details.
He is also able to compel people/things to do something with an enhanced loud voice.
Evvy compares Luvo's power to that of a thousand stones, however she also appears to be unaware of most of Luvo's power, discovering it only as he discloses certain abilities to her.
Luvo is able to see in the dark, although Evvy reflects that she is unsure whether Luvo does 'see'. When Luvo helps Evvy to view the sand in the beginning of Melting Stones, Evvy discloses that what she saw was unlike how humans see and Luvo explained that he can adjust his sight, and did so when he first met Evvy so that he could see how she saw. In addition to a powerful ability to 'see', Luvo has an automatic awareness of the land and around him. He is also able to know of coming earthquakes and the location of stones.
One of the most noticeable magical abilities of Luvo is the ability to speak- it is assumed that he does not have vocal cords or similar requirements. He is also able to change his volume, to the point that Evvy admits that Luvo can make his voice echo through her bones. Many people do not realise that Luvo is anything other than a rock until he speaks, and even then he is often mistaken for something more trivial than what he is, with some people referring to him as 'talking rock' and 'earthquake warning creature'. Luvo doesn't appreciate this at all.
Luvo's ability to maintain the plants, animals, streams, and other aspects of his mountain make him incredibly powerful. He easily blows a door off its hinges when he senses Evvy's distress. While the two of them are destroying catapult stones in midair, he pulls all the water out of multiple human soldiers, moves it into the cracks of the stones, and freezes it to break them apart. He can also collapse earth to create pits and cause avalanches powerful enough to completely bury a large fort. He can speak to the divinities and supernatural creatures that inhabit much of Gyongxe and request their help, and can likely talk to mundane creatures as well. He can see the magic within a human, and once the difference between ambient and academic magic was explained to him, he could distinguish these as well.
Each mountain has a heart who has the same potential as Luvo to interact with the world, however many mountain hearts do not realize those capabilities as they have to be prompted by great events. However, having been born from volcanoes, magma, and lava, they are weak to these things. Luvo is able to frighten two young magma spirits with his voice and trap them for a time by moving certain rocks into their path, but he would not survive a direct encounter with them, magically or physically.