The last person to write upon the Small Plates was Amaleki, the son of Abinadom. In relatively few verses, Amaleki covered a bit of history: "I will speak unto you somewhat concerning Mosiah." He wrote of the departure of a group of people led by Mosiah from the Land of Nephi and of their arrival in the Land of Zarahemla. He spoke briefly about the origins of the people of Zarahemla "who had come out from Jerusalem" at around the same time that Lehi and his family had left Jerusalem. Amaleki then wrote of Mosiah uniting his people with the people of Zarahemla and of Mosiah’s appointment as their king.
Continuing with the history, Amaleki wrote that later, his brother left Zarahemla with another group of people with the intention of returning to the Land of Nephi. Amaleki had no subsequent knowledge of his brother’s whereabouts. Having no other posterity, Amaleki prepared to give the plates to King Benjamin, son of Mosiah. Quite possibly because he delivered the plates to someone outside of Jacob’s direct lineage, Amaleki wrote more than his predecessors, filling all the remaining space on the plates with his personal writings. In his final words, Amaleki exhorted "all men to come unto God, the Holy One of Israel, and believe in prophesying, and in revelations." He spoke of the Lord from whom all good comes and expressed his concern on behalf of the people, admonishing them that they might be saved.
Once again, it is apparent that Amaleki completed his record on the Small Plates by using the command of the fathers (the instructions of Nephi and Jacob) as a controlling factor in determining the content and treatment of his text.
Book of Mormon Central, "Which Nephite King Had the Gift of Interpretation? (Mosiah 21:28)," KnoWhy 99 (May 13, 2016).