Kithood

Steelkit was born in ThunderClan to two well-known warriors, his mother named Ivoryrose and his father named Crimsonsteel. He was named after his father, wanting his son to carry on the legacy of the name of steel, as they came from a line of well-known warriors. Steelkit's father wasn't around very much, often using his time to go onto patrols and hunting for the Clan. He mostly stayed with his mother, while occasionally stealing materials from the fresh-kill pile to play with them. He'd listen to his mother's lullabies to fall asleep, or he'd hum a tune for her after another fight with Crimsonsteel.

One day, when Steelkit was almost an apprentice, he snuck out of camp after having an argument with his father. He was walking by the Thunderpath (although knowing about the stories about monsters on the Thunderpath) when he met an outsider cat, the same age as him. They talked and made fun of each other for a bit (Steelkit called the outsider 'strange'), and Steelkit questioned the necklace around the outsider's neck. After explaining what it was, the outsider cat told Steelkit about why he was out on his own. Turned out, the outsider cat was a kittypet whose owner died. Steelkit, without thinking, offered a place in ThunderClan. The new ThunderClan kit would then be named Strangekit, and they hung out with each other often in the nursery.

Apprenticehood

Upon reaching 6 moons old, Steelpaw and Strangepaw became apprentices, and Steelpaw's mentor was his father. Crimsonsteel was very strict with Steelpaw, and often trained till the sun rose. Steelpaw lacked sleep as he was very busy training with his father. His father continued to repeat his mantra of "Warriors are made of steel. Warriors do not show weakness." He started talking to Ivoryrose and Strangepaw less. Steelpaw started becoming more arrogant and some rude, using the excuse of 'training' if someone wanted to talk to him. All he could think about was training to become a warrior.

One day, Crimsonsteel got severely injured in a border skirmish, leaving him nest-bound for a while in order for him to heal. He should've felt bad, but for the first time during his apprenticeship, he was free from his father's chains. He'd started realizing what his father was really like and the trauma that he'd caused on Steelpaw; he didn't care about Steelpaw, he only cared about making a legacy. He remembered Strangepaw's necklace, and looking at the pile of materials by the fresh-kill pile, he could see something that could be made. With Strangepaw's necklace as a guide, Steelpaw made his own necklace. He gave it to his mother. And crafting became his new hobby. His skills improved over time, and he started making little trinkets piled in the corner of the fresh-kill pile. No one found out who had made them.

Word, of course, got to Crimsonsteel, who was still nest-bound in the medicine den. Steelpaw confessed to his father about his crafting hobby, and they got into a fight. Crimsonsteel said that crafting was a waste of time and that he should only focus on training. Steelpaw argued and said that he enjoyed crafting and training was important as well, but he wanted hobbies too. Steelpaw brought in the trauma that Crimsonsteel had caused him. They never spoke again after that. Steelpaw was reassigned to a different mentor named Trueheart to continue his training, and started talking to Strangepaw again, but he avoided his mother in fear of her bringing him to his father.

Warriorhood

Then came Steelpaw's warrior ceremony. He'd requested to the leader that his prefix be changed to Iron, to show the permanently cut ties with him and his father, and he was given the name of Ironmask. That same night, Crimsonsteel and Ivoryrose were out on a walk, and they were mysteriously killed by someone. Ironmask was devastated; while he didn't care much for his father, he still loved his mother. He vowed revenge on the one who killed his mother.