I'm not sure why they made a 3 min timer. Only thing i can think of is to make it more challenging for players. For some people that adds to the fun.
There is a rite called the Kincher rite that has timer too. Also, there is missions that are timed. It adds to the fun or challenge of the game. That is all I can say. :D
There is a rite called the Kincher rite that has timer too. Also, there is missions that are timed. It adds to the fun or challenge of the game. That is all I can say. :D