There are a total of 38 Data Core Doctor Who Cards in the game of which 30 are unlocked one by one as you progress through each stage of the Adventure Game. The other 8 cards which are listed below are unlocked by playing the mini-games and reaching the indicated score.
Unlock Auton and Tallulah: In Cyber Sequence score more than 25,000 points.
Unlock Judoon Captain and Brannigan: In Interrogation score more than 25,000 points.
Unlock Novice Hame and Sisters of Plenitude: In Memory Matrix score at least 25,000 points.
Unlock Sycorax and Ood: In Hi/Lo score more than 25,000 points.