Karan started his training with Lord Parshuram. Lord Parshuram was impressed with Karna's talent and dedication. Though he did not receive any proper training, he still knew the basics just by watching the soldiers of HP. 3 years passed and Karna not only excelled in archery which was his first love but also in swords, axes, spears, mace as well as hand to hand combats like wrestling, Kalaripayattu etc. Karna as he was a demi-god was 20 times stronger than normal human beings. But one thing that impressed Lord Parshuram most was that Karna's respect for his opponents. Even after beating his opponent he never disrespected them. Lord Parshuram with his divine power created many illusions to fight with him, but Karna was able to defeat them all.
Next Lord Parshuram started his training on Shabdvedi arrows. He blindfolded Karna and asked him to do his daily works using his hearing and his instincts. At first, Karna felt some difficulties but then used his sharp hearing ability to complete his works and training. Lord Parshuram's training made his hearing so accurate that just my listening he could distinguish among the source, distance, and position accurately.
After 3.5 years Karna became master of weapons, then Lord Parshuram taught him many advanced divyastras. Karna excelled in those training as well. He also learned about war strategies, vyuh formation. Karna himself was very creative and sometimes his ingenious idea even stunned Lord Parshuram.
Lord Parshuram (in mind),' All my students just used the knowledge that I taught them blindly. Nobody cared to try something new, but this boy is a genius. He is inventing his own strategies and vyuh formation models. May Lord Shiva saves him, who is going to fight with Karna.'
The next phase was the knowledge of Brahmastra. Lord Parshuram taught him about those weapons. Then he told him, ''Putra to become the master of these astras only knowledge is not enough. It is not very difficult to use those weapons but one has to know how to control and most importantly how to take those astras back or nullify their effect. Brahmastra is like a sentiment weapon. It chooses its master. If you want to have complete control over these weapons you have to do Kundalini sadhana. We have 7 chakras in our body which controls our life force. Those 7 chakras hold immense power but for most of the people the chakras are inactive. If you will be able to activate all of them, then you can not only control any weapons but also attain control over your Ripus. Every man has 6 enemies that take them to the path of adharma, they are Kam (lust), Krodha (anger), Lobha (greed), Mada (arrogance), Moha (delusion), Matsarya (jealousy). By successfully finishing this sadhana you can master over your mind and body.
From the next day, Karna started his penance. He diligently did all the rituals and after one year he was able to activate all his chakras with his yoga shakti.
Almost 9 years were passed and one day Lord Parshuram told Karna, ''I am very happy with our progress. I taught you almost everything I know but there are some things that I cannot teach you. There are many astras and techniques that are known by Daityaguru Shukracharya. I want you to learn that knowledge from him.''
Karna, ''But Gurudev, will he teach me. Asuras are always against Devas and humans.''
Lord Parshuram, ''No my son, a true guru will never discriminate among students. For a teacher what matters most are talent and dedication. Tomorrow he is coming to meet me. I want to you to convince him to teach you.''
Asurguru
Shukracharya, ''Pranipat Lord Parshuram''.
Lord Parshuram, ''Pranipat Asurguru, How are you?''
Asurguru, ''I am good, but I did not come here to exchange pleasantries. I came to see your student.''
Lord Parshuram, ''Why do want to meet him?''
Asurguru, ''I came to know that boy is going to be the downfall of Bhayankarasur. I want to know who has the ability to achieve the impossible.''
Then Karna came there. ''Pranipat Guru Shukracharya''
Seeing Karna Shukracharya thought, ''This boy is really strong. He has radiance like Suryadev himself while a gentle aura just like his mother Sangyadevi. I already warn that stupid Bhayankarasur, not to mess with tridev and mother earth but he is not listening to me. He is so arrogant that he is even insulting me, but I am the Guru of Asurs, so I need to do something to prevent this boy from attacking Asurlok.''
Asurguru, ''son Kalyan ho,'
Karna "Prabhu I want to learn about asurastras from you. Can you please teach me?''
Asurguru, ''From your teacher I came to know that you already mastered Divyastras, then why do need knowledge of Asurastras. Do you want to conquer Asurlok?''
Karna, ''No sir, I don't want to conquer anything. I only want to protect. I know asuratstras are used to create illusions, mayas and can hypnotize anyone. I want to learn those.''
Asurguru, ''But my son, Asuras are naturally protected by the effect of asurastras, but you are mortal. If you try to use those weapons, you yourself will fall for the illusions.''
Lord Parshuram,'' Asurguru, he already mastered Kundalini vidya and opened his chakras. No illusions can harm him.''
Asutguru, ''You are a very talented boy. Okay, I will teach you but in exchange, you have to promise me that you will never attack any asuras or asurlok.''
Karna, ''But what if an asura attacks me?''
Asurguru, ''If any asura attacks you or your family or your home, only then you will fight and kill the asur. Promise me.''
Karna, ''Okay Gurudev, I Promise''
Next Karna took training from Asurguru for 2 years After the completion of his training Asurguru gave him a special asurastra called 'Adityastra'.
After completion of Karna's training Lord Parshuram was so pleased with his achievement that he gave him Vijya Bow and Varghav astra.
He also blessed him saying'' Karna, you are the best student I have seen so far. I am blessing you, no warrior in Aryavart can defeat you. Even no devas or asuras can also defeat you, except for the tridevs and trideviyas. I am also pleased with your devotion to your Guru. Even in Kaliyug people will give the example of your Gurubhakti. But now it's time you shall know about your parents.''