The term describes a tool designed to assist players of the Pokmon Emerald video game in locating Feebas, a notoriously rare Pokmon. This tool typically involves algorithms or programs that analyze or predict the random number generation (RNG) of the game to narrow down the possible locations where Feebas might be found on Route 119. These locations are specific fishing tiles within the route.
The creation and use of such tools stem from the significant difficulty associated with encountering Feebas through conventional methods. Feebas can only be found by fishing in six specific tiles out of the hundreds available on Route 119, and these tiles are determined randomly upon starting a new game or mixing records with another game. This limited availability and random selection make locating Feebas a time-consuming and often frustrating endeavor for players. Therefore, calculators offer a method to potentially reduce the search time and increase the efficiency of finding the desired Pokmon.