Kundavai was also an imaginary character. The first kundavai was veeman kundavai of cholas.
Nothing much is known about narasimhavarman other than his vaatapi conquest. Most of his time should have been spent around this single activity. Only Thirukazhugukundram and few other places carry his inscriptions.
> How authentic is the Vikrama Cholan, being Son-in-Law of Narasimha > Varman I? Any evidences?