The recap of the events of part 1 includes a clip in which Oscar, Steve and Mahmoud are discussing an evacuation of "the city". This scene does not appear in part 1.
The probe crashes through a concealed platform covered with a thick layer of camouflaging dirt, sending up clouds of dust and debris, yet the probe has virtually no dirt on it when it is sitting at the bottom of the pit.
Large dark empty cavity revealed behind the wall of earth that the probe blasts through with its laser. Obviously a pre-hollowed-out area behind the wall of the pit that the probe moves into and completely disappears.
Straight edged seams are clearly visible in more than one place in the false pit wall materials prior to the death probe entering it.
There are a couple of noticeable jump cuts in the scene where Steve and Oscar watching the Death Probe remain still and act "confused." If you watch the branches in the foreground, they will quickly go from down to up, indicating there was a break in filming.
Each time Steve and Oscar return to the base camp in the yellow jeep, the green backdrop is noticeably fake. They in actuality are driving onto a mock up set.
After the bulldozer battle the Probe rides off. Tracks are already in dirt from previous take.
When they are using a map to try and track where the probe is heading, the map they are looking at is for Colorado, as the county names are quite visible (Larimer, Weld, Boulder, Morgan, etc.); in fact, the "x" on the map appears to be about where Garden City is in Weld County (they refer to it here as a fictitious "Brannon City"). However, in Part 1, they established that the probe had been found in a desert area near San Bernardino, California, and not in Colorado.