Two years.

Lich lived in that same forest for two years. In two years nothing much changed except the fact that now a lot of people had what they call Meta Abilities. Lich and his adopted siblings became not only older but also more powerful... First I will go one by one on changes on his siblings.

His first sister (3 years old), the same baby he saved from the researchers, he named her Sapphire because she had blue eyes and a collar with her when Lich asked her where she got that collar she said it was inside her belly or something... But at the end that didn't hurt her, so she was safe. Her personality is very agitated, she can run around, jump, climb, cut things, and more. She also likes to play with Lich in any animal form that he changes to! Her quirk became very versatile, she became able to stretch her arms and legs to run faster or climb tall trees, and even enchant her vocal cords to scream louder... She is an expert in hide-n-seek, she is able to hide pretty well and with her quirk, she van find anyone, except for Leon.

Leon is the bit who changes color, he is now 7 years old, his personality is very quiet and calm, he likes to read books just like Lich, but he is more sociable. Lich stole several books for him and also taught him how to write, read, and speak in other languages that he knew, such as English, Japanese, Portuguese, Latin, and Chinese! Leon easily called Lich Aniki, Lich taught him this word and he never stopped calling him that... His quirk is quite simple and complicated... He can change the color of his skin, hair, eyes, and even change the smell of his body! Playing hide-n-seek with Sapphire he quickly learned how to use his quirk to hide, he can become invisible too if he focuses on reflecting light, another thing he can do is climb. But not normal climbing! His hands and feet can stick to walls and stuff! Isn't it cool? Anne calls him Camaleon because he sometimes changes his color because of his mood.

Anne is the girl with horns. She is 6 years old now, her quirk is very simple too! She can shot horns out of her head and control them with her mind! She can throw up to four horns, they are very resilient and resistant to damage that she can break rocks with it easily! She can also alter the size of the horn before she shots it out of her head! She likes to shot big horns so she can ride them and fly around. Her personality is playful, she likes to prank people and is a tsundere with Jun, she likes to challenge him and Lich to flying competitions across the forest that Lich always wins.

Jun is the winged boy, he is 8 years old now, his personality is more responsible and mature, much like Lich he likes to observe his siblings and play with them. He has a rivalry with Lich and wants to win against him in everything, they have always a competition at least once a day. His score is 0-500 with Lich winning everything. His quirk is simple, the wings in his back can grow or shrink, he controls them with his mind and they are a part of his body. He can fly around and even use them as a weapon because the feathers on his wings are harder than iron but not heavier as such. Even when competing against Lich and losing, he never stops trying. He respects Lich because of his strength and is a battle maniac a little bit...

This tale has been pilfered from Royal Road. If found on Amazon, kindly file a report.

Lich is now 10 years old. His body grew taller and he still doesn't like to wear clothes. He went to civilization (aka the Super Market) several times in these two years, he was sawed by several people and even some people tried to kidnap him, so he killed some here and there and escaped others. Because after his 10th birthday, a small horn appeared on his left side of the forehead, this horn is small and he doesn't know what it does at all... It sometimes just hurts and grows, nothing much. His control over his quirk increased so mucht that he is able to somewhat create a vacuum by simply removing all the air around him and accumulating it in one single place, and then realizing... This caused a huge fucking explosion that almost killed him. He also was able to switch between transformations at will, this made him create fighting for himself. He is not only able to change his body to an animal, but he is also able to change some parts of his body, like growing nails and transforming them into iron.

It hurts, like a lot, but he doesn't even flinch while doing so. His quirk is so versatile that he can even transform someone into an animal for some time! He can control every inch of his body with his quirk and become a slime or even become rocks or iron bars. But he can still be attacked and killed... He started to train his siblings, but with the excuse that it was a game, like a game of tag, for example, they would dodge each other and run around, exercising. Hide-and-seek trained them to become one with the environment... And there was this game they did once a month, they had to touch Lich. If they did, he get something for them, if they didn't they would need to run around for hours. Sometimes they would win, and sometimes they would lose. But when they would win, it was Lich letting them win. Because he can change into other animals while fighting! And even humanoid-animal hybrids, like furries. I will give you an example:

Lich is fighting against a gangster that has a quirk. His quirk is a normal quirk: Teleportation. He can teleport small distances. The gangster has a knife as his weapon while Lich only has his body as a weapon. The combat starts with the gangster teleporting to Lich's back and using his knife to stab him, Lich then transforms into a Pidgeon and dodges the attack flying up, while he is up he transforms into an elephant to try and stomp the gangster that teleports four times to dodge. Lich changes back to human and changes again to a human-leopard hybrid, charging towards the gangster who teleports away and throws the knife at Lich who transforms into a humanoid-octopus and with his hand transformed into a tentacle, he uses his quirk to change his tentacles. Now they are iron tentacles with very sharp blade-like bones on the edges of it. With two tentacles arms, he can fight and easily kill the gangster. But he can also create more and more tentacles, he can also use the elements, and heal, and drain life from people, animals, and plants. So, who was going to win that fight? Yeah. Lich is pretty hard to defeat.

And there's also the horn in his left side of the forehead that he doesn't know what it does. He can't control it even when using his quirk. It just stays there... Somewhat he feels like this horn has nothing to do with his quirk... Like it is completely different from him. Like... A second quirk that he doesn't know how to use or activate. His siblings say that they can turn their quirks on and off, except the horns and wings obviously. He really wishes his horn does something, maybe he can use it if he trains real hard.