Along with the achievements that posted as titles and gamerscore points for them, there are those secret achievements that you can also earn with the game of Bioshock. These are the secret titles that you can earn and the gamerscore points associated with them.
Defeated Dr. Steinman – You will have to win over Dr. Steinman to earn this title and 15 gamerscore points.
Defeated Peach Wilkins – You’ll need to win over Peach Wilkins for this achievement and 15 gamerscore points.
Defeated Andrew Ryan – You’ll have to win over Andrew Ryan for this and 30 gamerscore points.
Completed Cohen’s Masterpiece – You will have to finish Sander Cohen’s masterpiece of this title and 30 gamerscore points.
Restored the Forest – To get this title you will need to restore the forests of Arcadia and then you will get 15 gamerscore points.
Defeated Atlas – You’ll have to win over Atlas for this achievement and 100 gamerscore points.
Broke Fontaine’s Mind Control – Exactly as it states, you’ll need to break Fontaine’s mind control to get this title and 30 gamerscore points.
Irony – You need to take a pic of Sander Cohen’s dead body for this title and 10 gamerscore points.
Became a Big Daddy – You will have to be a Big Daddy for this title and 30 gamerscore points.
Found Cohen’s Room – You will have to enter Sander Cohen’s private room for this and 10 gamerscore points.
Brass Balls – For 100 gamerscore points, you’ll have to complete the entire game on hard setting without using a vita chamber.
As you can see there are even more secret achievements that you can earn and gather even more titles under your gamertag on the XBOX 360. For those that like to collect as many titles as possible, these add even more to the basic Bioshock achievements that you can earn. Good luck in getting as many of these as you can and maxing out your gamerscore points too!