Tier 1: Defend The Marya Barricades
Another Defend a location mission. You should be very familiar with these by now. Wave after wave of cultists will come at you, and you will beat them to a bloody pulp each time.
Tier 2: Destroy 2 Reinforcement Trucks
Whenever you attack a truck, the group of Cultists standing by it will charge at you to defend their truck. Kill them before proceeding to blow up the vehicle. Repeat for the second truck.
Tier 3: Use The Mortar to Destroy The Truck & Defend
Use the Mortar to blow up the reinforcement truck on the opposite side of the bridge. Click on the mortar, position the target so that the green part falls onto the truck at some point, and fire away. You can either stay up here and use to Mortar to defend for the rest of the waves, or you can go down to the ground level and fight the cultists normally. If you have a friend, one of you can stay up top and mortar enemies, while the other stays downstairs and picks off any that may not die.
Tier 4: Kill Defilers, Polluters & Find Source of The Filth
Round up the enemies and make them go boom! The source of the Filth is at the smaller red circle up ahead. You can’t miss it.
Tier 5: Block The Darkwells & Defeat the Reborn Monstrosity
Collect explosives from the crate of explosives(obvious, right?) and Head in towards the mission markers. Hug the walls because if you stand in the Filth, you will get a dot(damage over time) on you that can be nasty when it stacks up to a high enough count.
Each detonation spot will be against a wall. Just plant the charges and wait for the explosion.
Be sure to pick up “Filthy Science” after you kill the Reborn Monstrosity.
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