Having trouble with time trials? Complete the last time trial in Bolivia against the final boss first (it's a boss fight, and it's easy). This unlocks the one-hit death cheat. You can input the cheat when the cinematics are playing at the start of a stage and make enemies and certain bosses die quickly, saving you some much needed time. It also makes the motorbike races faster to finish. Note that only one cheat may be turned on at a time.