Head to the foundry. Stay behind cover and very low at all costs. Using the Assault Shotgun will be extremely useful.
Swap to Michael when prompted and clear out the catwalk. After Lamar calls, use Franklin, get out from cover, run to the catwalk, drop off the end, and go out the door by the control office. Use the car for your cover and kill the enemies. Swap back to Michael. Sweep out the center of the room, pass across, and hide behind cover next to Trevor. Survive another wave of enemies, then switch to Trevor.
Eliminate all enemy attack inside. Rush outside using Michael and beat the enemies attacking Franklin. Utilize rockets to hit incoming vehicles. Sweep out the upper levels in the distance using the MG. Circle around the building, hiding behind cover. Shoot the guards around this area and blast away the choppers.
After escaping, as Franklin use a bike to inch closer to the convoy. Shoot the center car with bullets as soon as it hits the highway to scare it to stop. Circle around the ridge along the highway.
Utilize rockets to eliminate the boss. Swap to Trevor. Using a car, go through the park gate and down the midway, stopping halfway to the Ferris Wheel. Utilize a sniper scope to find the FIB agents, then switch to a rocket and take out the car. Get back into your vehicle and go out.
Keep driving right up to Stretch and co. Get outside the car, use Michael’s special ability, and just minigun everybody. Swap back to Trevor, Methodically approach the house from the front gate, then go around the left area of the house. Tap fire to keep the minigun spinning, then hold it down once you see a target or rounding a corner. Utilize Trevor’s tank ability when needed. Find Devin hidden in a basket beside the pool. Take Devin to the coast.
