Little Sisters

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Little Sister
A 'posessed' Little Sister, harvesting ADAM.

"Look Mr. B., an angel!"

An experiment created for the purposes of harvesting ADAM, the Little Sisters largely represent the morality aspect of the game. Upon destroying a Sister's guardian Big Daddy, the player can choose to harvest the Sister for a lot of Adam (and hence Plasmids, Tonics, and everything else the Gatherer's Garden offers), or rescue them for less (but with rewards from Tenenbaum for every three rescued).