Act 2: Nightfall

When you go inside after the split, allow the player who follows the left route to collect the nearby ammo and Frag Grenades before the other player approaches the balcony and triggers the Boomers’ arrival. To deal with the Boomers, have the player on the balcony dive into cover and blind-toss Frag Grenades over the railing.
The two teams emerge from the building on opposite sides of the chainlink fence. The team on the right-hand side must quickly take out the Sniper in the building, and then lend a hand to the teammates on the left. When the left side is cleared, that team should advance under the overhang. This puts them in perfect flanking position for the Locust exodus from the building on the fence’s right side. When it’s time to take out the Troika, issue the “Attack” command to have Baird and Gus advance on the Troika and flush out the Gunner from behind his post.
On the bridge, both players can push the car toward the Troika. Stick together while one player uses a Frag Grenade to kill the Gunner. This allows you to revive one another if necessary. With the Troika silenced, split up and sweep forward toward the Emergence Hole; one player takes the left side of the street and the other takes the right.
On the ferry, have the player that’s not cranking the wheel snipe the fluorescent lighting along the path. Pitting the Kryll against the Drones is especially useful on the harder difficulty settings.

The journey to Chap’s Gas Station plays out very similarly in Co-Op mode. Advance cautiously and have one player hold onto the Longshot to take out distant lights located above the enemies. Keep to separate sides of the street and exploit one another’s positioning as you detonate the propane tanks. This minimizes the amount of time each of you spends away from cover.
When the battle at the gas station begins, both players should hunker down inside the station’s office and ready the Frag Grenades. Toss the Frag Grenades over the median in the street to eliminate as many Drones and Grenadiers as possible during the initial crush. You can snipe the second batch of enemies from a distance as they emerge near the Junker. Lastly, once you defeat the Boomer, move behind the barrier in the middle of the street to snipe the remaining enemies.

Marcus drives while Dom operates the UV Turret. Remember that shooting the turret stops the Junker. Drive the car slowly to maximize the distance between the Junker and the Kryll at all times—don’t inadvertently hurry toward them. Once you locate the Kryll, have Marcus drive away from them, whether it be forward or backward, in order to maintain a gap. Most importantly, heed Chap’s reports on the directions from which they’re coming.

As soon as you reach the Stranded, have one player immediately run to the Troika while the other heads through the window inside to close the first Emergence Hole. This player should then gather the Frag Grenades and join his partner. While one player continues to operate the Troika, the other must focus on closing the Emergence Holes and then shift to detonating the leaking gas pipe and dropping the concrete slab. When it’s time to destroy the final Boomers in the massive Emergence Hole, make sure both players are safely behind cover near the building, ready to shoot the propane tanks as soon as they are visible.