SPLOICERS
What you mean the good ending? Not the best possible. I actually preferred the evil ending myself :/ What difficulty did you beat it at? I beat it on a hardcore with all the achievements :D
*INSERT ENGLISHMANS VOICE HERE*DONT WURREH, UR GENETIC CODE IS BEIN REWRITTEN
Bioshock is one of my favorite shooters, and I don't know what you mean "Best possible ending" because there's only two and it's kinda based on personal preference if you like killing children or not.
Actually there are 3.Kill 1 child or less: Good endingKill more than one child but not all: Mixed endingKill all children: Bad ending