Chapter 5 - Bon Voyage
To compensate for the last chapter being short, this one is long. You have two collectables to find and one COG tag to grab. The chapter opens with you finding your submarine. Time to get it fueled up and see if Dizzy can start it. Turns out that it he can't. You need to get fuel and a new rotor. You're given the choice of which to search for. Search for the Rotor if you want the first collectable.
Wretches ambush you, of course. You should really expect it at this point. You'll fight them off and tickers will join the fray, and later on more upright Locust varieties, like boomers. Eventually you'll reach an elevator to carry you up. Up top are even more Locusts to take out. When you reach the area the Rotor is in, you can find the Bulletin in an out of the way corner. It's one of the collectables for the level. Clear out the Locust and deliver the Rotor. If you're in the Loader you've gone too far, but you can still backtrack.
You'll have to blast your way through some more Locust with the Loader, along with some reavers. Try not to get your loader destroyed, otherwise you'll have a hard time keeping that Rotor where you need it.
Once you kill a few more Locust you'll have to head outside and find the docks. Before you go, there's a shipping container with a COG logo on it. Behind it is a COG tag. Only a few more to go!
Next you get to pilot a Silverback and blow up a selection of Locust, from reavers to royal guards on mounts to turret-users. The fuel you need is on the ship they're defending. Take out the Locust and you'll be able to send the fuel back. Through, of course, even more Locust defenses. Defend your fuel with a selection of weapons from the Silverback, the turrets, and a Hammer of Dawn lying around.
Now you need to escort the sub out to the docks. In the second storage door you pass through, head up to the second floor. Upstairs, if you look just inside the door on the floor, you can spot the last collectable of the Act, the Contractor Report.
The boss of the area is the Armored Kantus, the three dudes you saw earlier being ordered to stop you by the Queen. The second wave includes Serapedes, and everything just soaks up your ammo without being damaged much. Use explosives when you can. For the Serapedes, shoot their tail segments and blow them up piece by piece. Defeat all of the Kantus and the act is over. One more to go!