Destroy All Humans! Big Willy Unleashed - PS2 PSP WII/Quick Strategies

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Map

Note that when not in a mission, Green Circles on the map are Odd Jobs (side missions) and Yellow Markers are Story Missions. What's odd is that the Story Mission will produce Red Beacons in 3D environment. Just make a mental note as to not get too confused.

Energy Cell Hunting

Scouring a level for all its Energy Cells can be daunting at first. Each level has a lot of nooks and crannies to hide the little buggers in. It's considerably easier to search for these pieces if you activate the unlockable Zombie Jamboree or have beaten the game and can trigger a Furon Invasion. Either will distract the humans so you can rome pretty much freely without much interference. Another big help in your quest will be to simply level the entire landing site. Buildings, structures, trees, rocks, anything that is standing should be taken down to the ground. Using the Saucer's Q.D. will make quick work of any of the levels. Flatten the level then hop out and search on foot should help find any last hidden Energy Cells.

Big Willy Recharge

Once you acquire the Ball Lightning, taking the time to pick and eat humans is not really worth it anymore. Simply use Big Willy until he's out of juice, then hop out and shot him with a Ball Lightning to almost instantly recharge him. It's a lot easier and quicker than having to worry about grabbing humans all the time.