Predator: Concrete Jungle

In the Dead Men Walking level, you can see a poster of Uncle Sam on the sides of the Sanctuary.

After completing the timed section of the mission, locate three pick-up trucks with weapons on their beds. Destroy all three. Two of the vans are near the multi-tiered parking structure where the Predator started the mission. The last van is parked on the street next to some of the gang cars.

On the roof where El Hongo walks down a ramp, go towards the first recharge point. There will be a white marker on your map. On the street will be a cop with a marker on his head. Scan him in tech-vision. For his gender scan, it will be a female.

Kill all snipers in the mission A Night to Remember.

Destroy the large computer at the start of the mission The New Flesh.

Kill 50 aliens in the mission Bug Hunt.

Ignore the first enemies and kill a man instead on the mission Extinction.

Kill the Irish boss in the mission Midsummer Night's Massacre.

Destroy the three trucks after following El Hongo. The first truck is by a billboard at the start of the mission. The second truck is in a carpark, and the third truck is at the southeast edge of the level.

Note: Weapon upgrades are cumulative and you do not need to get them in a particular order to "up your guns". All weapon upgrades are out in the open (never in a box) and are usually just hard to find.