The leathery protrusion on the egg should be handled with extra care, as it holds the creature's actual heart inside. Piercing the pulsating skin would cause the creature to die, as well as you, as the blood of a Fierha, especially taken from the heart, is highly flammable. So the morale of the story? Handle this egg with extreme care!
Every spring thousands of Arkians adopt a baby Fierha to their family, unable to resist the charm of their pup form. Most of these do so lacking any knowledge or consideration, so they're up for a big surprise when the creature grows three times its original size and can bite straight through metal. Scared that their pet is beyond their control, many people, sadly, abandon their Fierhas. And those that don't do it at this point are still likely to do it later, when the so-called "cinder-fur" on the creature's back catches permanent fire, being fueled by the blood of a Fierha's heart.
The people that get a Fierha deliberately, though, and are able to raise it properly, don't need to fear for their lives ever again. There is no creature more loyal and ready to fight for their master than a Fierha. Without any danger in sight, the thing that makes them the most happy is to see their human friend happy. Many of the longtime Fierha owners claim they have such a complete understanding with their fiery companions they don't need to speak anymore. In such a pair, older-aged Fierhas might undergo the final transformation - their heart bursts, turning into an ever-burning ball of fire. The properties of that fire change, too. Instead of blazing flames the creature's now shrouded in evenly glowing light, which does not burn the person the Fierha is connected to and cannot be doused. It is a common saying in Ark to describe a longtime couple that's still visibly in love: "They glow like a Fierha on a dark Autumn night".