A special ability or event labeled with the word “Response:” indicates that you may perform that action whenever the trigger described in its game text happens.
You may respond more than once to the same situation.
A response action is not a phase action (because there is no “response phase”).

Of course there is the theory that all these spoilers are fake and that the real cards are much better and less OP.

According to the comprehensive rules book 4.0 Response entry:
A response is a special ability. Therefore once the free people’s player has paid the costs of adding two threats and spotting the wizard, you cannot use any responses or other phase special abilities until the regroup phase.

In response to foresight the action has to complete before it can be responded to unless there is the trigger "is about to". The effect takes place but would later be canceled by final strike. Unfortunately, the effect of Perspective is such that it prevents the prevention.