What this magic does is easy to guess by its title, it fires rock shards like in a direction like projectiles, one of the most basic earth magic of all. Asutrix reason for teaching him this instead of a easier magic is because the other spell was a defensive one, Earth Wall. Only knowing this spell all Adam could do in a fight would be hide behind a wall until his mana run his out, in other words, nothing. And that's if the enemy is retarded and can't just attack from another direction ignoring the wall.
After resting for some minutes after the knowledge transfer, Adam set out to collect the materials to cast the spell. Yes, that's right, materials. Some spells needed materials to be casted, the majority of these spells being of the metal element, a rare earth element variant. All Adam needed was a stone, nothing complicated.
Adam soon found a stone in the ground that was slightly smaller than his palm, and found a tree to test the spell on. He started casting the spell on a ancient language, ancient elvish, elves were the first beings to use magic without being born with it.
Following Adam chant, four shards separated of the stone in his palm started to levitate in the air with a white aura-like thing surrounding them. The stone still had more shards left, but Adam felt like four was his limit. After the chant ended, Adam pointed his palm to the tree in front of him, and the shards set out in a very fast speed towards it like arrows. All the shards stopped halfway in the tree, wich was slightly thicker than a human waist.
"Wow!!" Adam fell down to the ground panting from tiredness, but he still was amazed by the shards power.
"Hmm the stones were fast as arrows, and there were only four shards. Nothing too incredible but considering this was your first time casting a spell, you have some talent. And congratulations brat, you are now officialy a Mage Apprentice." That was Asutrix comment seeing his spell. Adam didn't know that but Asutrix knowledge and his talent in earth magic helped him greatly.
A normal Apprentice needed to study the spell they wanted to learn a lot first then to try to cast it, wich had nearly a hundred percent chance of failure, casting the spell on the first try was nearly unheard of.
"Why I am so tired....*Huff*." Asked Adam seeing his body condition.
"That happened because you used all of your mana, wich leaves you tired like that. See? Don't waste mana in a battle or you could die." Warned Asutrix.
"Sure.. And that part about becoming a Mage Apprentice, how did I became one?"
"Everyone has mana, wich is in the air, in our bodies and so on. The ones wich are capable of using their own mana to cast spells are Mage Apprentices. The ones capable of engraving a spell circle in their mind are First Ring Mages, this goes until the ninth ring and you don't to worry about that for now, and beyond the ninth ring is a Archmage." Asutrix explained the Mage levels for him.
"Wait, what do you need to do to become a Archmage?" Adam was curious.
"Heh Heh, you don't need to care about that now brat. You have looong way until there." Adam felt like Asutrix was smiling again. Well, he was curious but not so much, so he decided to let it for later.
"Brat, go to sleep. You are out of mana so you need to either meditate or just rest like normally to have it again. And since your level is so low, you can't miss sleep, go back to the inn." Said Asutrix.
Adam was really wanting to sleep since casting the magic, and after hearing Asutrix he decided to go back to the city and sleep in his room. Asutrix said he would teach him meditation techniques tomorrow.