Answer

Bhagwan Mahavir Swami performed many severe tapas, but if you are asking specifically about Athai tapas—fasting for 8 continuous days—the traditionally mentioned number is:

Mahavir Swami did 12 Athai.

Explanation

During His sadhana period before attaining Keval Gnan, Bhagwan Mahavir practiced very intense austerities. Jain tradition describes His tapas as extremely difficult and disciplined, including long fasts, deep meditation, and complete equanimity.

Spiritual Understanding

Mahavir Swami’s tapas was not for showing physical endurance. It was for:

• Destroying karma
• Strengthening complete detachment
• Remaining in perfect equanimity
• Progressing toward Keval Gnan

Takeaway

Bhagwan Mahavir Swami did 12 Athai, and His life teaches us that true tapas is practiced with inner purity, non-attachment, and equanimity.