- It seems like Kotal isn't hostile to Shao Kahn at all. His own people were defined by Kotal as warriors and conquerors, so he won't feel like a victim or a poor little good guy since they did the same thing themselves while they could.
When their kingdom fell, all we saw from Kotal was that he felt embarassed that his father surrendered. But he never said anything against Shao Kahn and by the look of things he respected him as a mighty conqueror figure. Most importantly, once they surrendered Shao Kahn accepted it and lept them keep their crown and autonomy and even their magic stone thing, so there was no extermination or anything.
During all the time he was by himself and in his returns to Outworld, he was always going about his amazon tribe and his father, he showed no intent of revenge to Shao Kahn. Furthermore, in his speech in Outworld he clearly says usurper Mileena drove Outworld to the brink of disaster, which shows he respects the might of Outworld under Shao Kahn and Milleena was ruining that legacy. There's also the matter of him taking the Kahn name as a sign of being a successor and a continuity.
