Is Half-Life (the original), System Shock 1/2 or Deus Ex the most revolutionary within their genres?

Hi all,



I played Half-Life and finished it when I was just 8. Drew a line suffice to say.



Then Deus Ex came out when I was 11 or something, and was just as incredible as Half-Life was but it was an RPG.



Funnily I played System Shock last, was more into the fallout series in that period.



I speak as a wholesale and utter fan of all three.



What I'm saying is - which game made the greatest influence In it's time and genre relative to eachother?Is Half-Life (the original), System Shock 1/2 or Deus Ex the most revolutionary within their genres?
Out of these 3... I would pick Deus Ex