An attempt is made to present a short sketch about the unique patterns of formation of personal pronominal forms in Mohanpuri, a dialect spoken across Bengal-Odisha border in India. The study is based on a large collection of empirical data and information elicited from the native speakers of the dialect. In the history of this dialect, this is the first attempt which adopts the methods of modern dialectology in the act of dialect data collection and analysis supported by extralinguistic data and information retrieved from the informants through direct interactive elicitation. This is the first study which shows that the dialect is on the verge of extinction due to the heavy influence of Bangla and Odia. It carries a large set of unique features in the formation of pronominal forms through the spontaneous use of Bangla stems and Odia case markers to serve the process of pronoun formation. Strikingly, the morphodynamics involved in the formation of such forms in this dialect generate a large list of pronominal forms, which are neither Bangla, nor Odia, but a type of a new kind, which are unique in orthographic representation but similar in lexicogrammatical function at par with the pronominal forms of the influential languages. Contrary to traditional linguistic observation this study shows how pronominal forms, which are assumed to be rigid to undergo changes, have been mostly transformed through a portmanteau combination of stems and inflections. This also substantiates our argument that morphological metamorphosis, after phonological assimilation, can manifest itself in the linguistic behaviour of a dialect community but may not percolate to other domains of language use (i.e., syntax), even though such pronominal forms are frequent in use in all kinds of syntactic constructions available in the dialect. Through an elaborate study of various aspects, properties and features of the pronominal forms used in the dialect, it is possible to provide a kind of sustainable help for protection and preservation of this dialect. This study may be considered as a service for the protection and preservation of one of the endangered Indian languages and its culture, which has been quite vibrant for generations before it is pulled to a state of survival crisis.