Akash Kumar Choudhary has scored first-class cricket's fastest fifty off just 11 balls (beating 12), including eight successive sixes (beating six).
He came in with Meghalaya already 576-6 against Arunachal Pradesh. Meghalaya went on to win by an innings and 446.
See full updated lists for fastest first-class fifties and most consecutive sixes, both now headed by Akash Choudhary, in the Records on our website:
https://stats.acscricket.com/Records/First_Class/Overall/Batting/Fastest_Fifties_by_Balls.html
https://stats.acscricket.com/Records/First_Class/Overall/Batting/Sixes_off_Consecutive_Balls.html