Atlas, the pseudonym of undersea smuggler Frank Fontaine, is another villain first introduced as your only ally in a hostile world. As the mysterious Jack, the player is dragged into the undersea dystopia of Rapture and becomes an inadvertent pawn in the power struggle that toppled the city.Adopting an Irish brogue to further disguise his true identity and using the plight of his fictional family as leverage, Atlas quite literally directs the player as they wander through Raptures dripping corridors, explaining the citys unusual ecosystems and acting both as saviour and tour guide. After his duplicity is laid bare in Bioshocks infamous reveal his radio goes sadly silent -- when the player encounters Fontaine in person hes succumbed to the lure of his own contraband and his hulking form makes for a final boss fight thats high on explosions but low on exposition.Atlas is the driving force of Bioshock; he engineers Jacks descent into Rapture and uses him like a puppet against the citys architect, Andrew Ryan. While its a shame that he largely disappears in the games final act, Fontaines duplicitous plan and the ensuing plot twist ensure he remains one of gamings most memorable villains.