After Corrin is brought back to Hoshido, they are reunited with their birth mother, Mikoto, and their Hoshidan family, the Hoshido royal family. This joyous occasion prompts Mikoto to announce to the Hoshidan people of their return. At Shirasagi Castle Town, as she introduces them, a hooded man pulls Corrin's Ganglari and uses it to induce a large explosion, killing numerous Hoshidan civilians and destroying the town square. He then uses shards from the blade to attack Corrin, but Mikoto jumps in the way and takes the attack. As Corrin holds their mother, she dies in their arms, causing them to awaken their Dragon blood out of grief. Lost to their rage, Corrin becomes a mindless feral dragon, bent on revenge. After the hooded man is forced to retreat, Azura uses her special pendant and a special song to quell Corrin back into their human form. Azura then gives them a Dragonstone, a special stone filled with the energy necessary to spur their transformation into a dragon safely without returning their feral state of mind.
Corrin's child, Kana, inherits Corrin's dragon blood. In their Paralogue, they are ambushed by invisible forces. Corrin makes a timely appearance and tries to fend off the forces. Unfortunately, they are swarmed and despite their protest to make Kana head to safety, seeing their beloved parent wounded, Kana degenerates into a Feral Dragon and attacks the enemy forces in their rage. After dispatching the enemies, Azura helps Corrin quell their child and gifts them their own Dragonstone to control their draconic blood.
The Feral Dragon class is technically a playable class as the player fully controls Corrin in this class in Chapter 5 of Fates. This is the only chapter in the game in which this form is playable. This heightened form boosts their current stats, though retains their HP base. As a Dragon Unit, they are especially weak to Wyrmslayers and Dragon Spirits. Kana, as an NPC in their recruitment paralogue, degenerates into this form for the chapter and has the same traits as Corrin in the form.
Help Description (Localized)
A ferocious beast that was once human.
Help Description (Japanese)
正体不明の竜。神の如き力を持つと伝えられる。 ("Shōtai fumei no ryū. Kami nogotoki chikara o motsu to tsutae rareru.")
Translation: An unidentified dragon. It is said to have god-like power.
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- Given that Anankos is the father of Corrin (specifically his human avatar, as seen in the Hidden Truths DLC), it's highly likely that the species the Feral Dragon class belongs to is the Silent Dragon, as it also uses water-based attacks in its move set and, judging by the Japanese help description, this is possibly left out intentionally to prevent spoiling the game.