The end credits conversation/text uses "realised" with the English US language setting, in US English "realized" is the proper spelling.

This occurs only once about two-thirds down in the line "Shush... Sometimes the player read lines of code on a screen. Decoded them into words; decoded words into meaning; decoded meaning into feelings, emotions, theories, ideas, and the player started to breathe faster and deeper and realised it was alive, it was alive, those thousand deaths had not been real, the player was alive"