During the time of Bhadrabahu swami there was a drought of 12 years and this knowledge started to disappear. In the lineage of Bhadrabahu swami there were 2 great Acharyas - Dharsen Acharya and Gunbhadra Acharya (around 700 years after Mahavir bhagwan - reference: 64 riddhi puja by Swaroopchandji). Dharsen Acharya Dev lived in the caves of the Girnar mountain. Until his time, knowledge was passed verbally but then he noticed that due to reduction in brain power, this verbal knowledge was diminishing and was afraid it would be lost altogether so he called 2 monks from the South of India - Pushpadant and Bhootbali. He tested them when they came, by giving them 2 mantras, one of which contained an extra word and the other one was a word short. Whilst both monks were thinking carefully about these mantras, 2 devis (fairies) appeared - one with one eye and one with one tooth sticking out. Thus they understood that these mantras were not pure. They added the missing word and removed the extra word from the 2 mantras, and as these became pure two beautiful devis appeared. They then took these two mantras to Dharsen Acharya who upon reading them said "Jai Ho to Shrut Devta" (long live correct knowledge). As he was satisfied, Dharsen Acharya gave them the knowledge of "the 5th mahakarma prakarti prabhrut adhikar of Agrayani poorva". The two monks then absorbed this knowledge and wrote the first scripture called the "Shatkhand Agam". On completing this scripture in the town of Ankleshwar on the 5th day of the Jesht Sud month (shrut panchami), the devs performed a special puja. From this scripture, many more scriptures were written and thus started the flow of written knowledge.
1000 years after Mahavir bhagwan was the birth of Kundkund Acharya. He is also called Kali Kal sarvagna and he has the highest position in the Digambar jain hierarchy - his name appears directly after Gautam garndhar in the manglik "mangalam bhagwan viro, mangalam gautam mogani, mangalam kundkundaryo, jain dharmastu managalam". He took diksha (renunciation) at age of 11 years and he sincerely felt the absence of kevali and shrut kevali. Coincidently, a friend from his previous life, a dev who was passing by Bharat chhetra felt sympathetic and took him to Simandhar bhagwan's samavasharan in Videh chhetra. When he reached there, because his body was tiny compared to the other persons in Videh-chhetra, the chakravarti asked who is this tiny human person? In Simandhar bhagwan's divine voice the answer came that this is a great acharya from Bharat chhetra who is subsequently going to spread the word of religion. After staying in Videh chhetra for 8 days, acquiring lots of knowledge, Kund Kund Acharya came back to Ponur hill in Bharat chhetra and then wrote Samaysar, Pravachansar, etc - a total of 84 scriptures.