In Dead Rising 2: Off The Record for the PC, PS3, and Xbox 360, there are a couple Zombrex vials that are hidden around the game that you can find for free instead of buying them.
Free Zombrex 1 – Underground, beneath Atlantica Casino, it’s on the ground if you go west from the entrance
Free Zombrex 2 – In the Uranus Zone VIP Lounge, climb out onto the awning and go left and you’ll see it on the floor
Free Zombrex 3 – On the roof of the Safe House, behind the elevator on the ground
Free Zombrex 4 – In Uranus Zone Bank, Security Box 999, the key can be found in the fountain in Atlantica Casino by the Fortune Park entrance
Free Zombrex 5 – In Uranus Zone Bank, Security Box 673, the key can be found in Fortune City Hotel on the floor near the entrance to South Plaza
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