13. Splinter Cell: Double Agent
Coming off of what is generally considered to be the best installment in the series, Double Agent would mark the first time that Ubisoft attempted to shake up the traditional Splinter Cell formula. Double Agent's opening finds Sam Fisher reeling from the death of daughter - who was killed in an automobile accident - when he's called in to infiltrate the ranks of the JBA (John Brown's Army), a domestic terrorist cell. After the initial meet, Sam is taken into the fold, and it's up to you to carry out your duties while avoiding discovery by the enemy. It's certainly an intriguing premise, and Double Agent takes full advantage of the setup by pitting your supposed loyalties to the JBA against your duties as an agent of Third Echelon, leading to some truly harrowing decisions. Suffice it to say, Double Agent was a different sort of Splinter Cell than most were accustomed to, and the emphasis on causality lent the game some serious replay value as it was possible to attain numerous outcomes depending on your decisions.