Read Prima's free inFAMOUS: Second Son walkthrough.
Tip: Prior to beginning this mission, save up as many Blast Shards as you can. Once you earn several Concrete powers from Augustine (Concrete Shrapnel and Concrete Barrage), use your upgrades to increase their effectiveness, making the final boss battle somewhat easier to win.
After taking out the power source to the tower, stay on that platform and engage the D.U.P. from a safe distance. After thinning their numbers, head over and absorb the Smoke before Smoke Dashing through the vent to the next level.
Tip: To avoid instant mission failure, do not fall off the tower. Even though it's scarce, there is normally cover on each platform. If you're in trouble, get to cover and heal up before returning to the fight.
When you reach the next platform, Fetch will show up to save the day. She'll fight alongside you, making things just a bit easier in the immediate future. Continue to work your way through the waves of D.U.P while ascending the tower.
Tip: If you earn the Comet Drop, Radiant Sweep or Hellfire Swarm, don't hesitate to use it. Once the final battle against Augustine begins, you won't have them available. Best to make sure they aren't wasted.
Before you can reach Augustine, two helicopters will interrupt your progress. Luckily, your other friend in the game, Eugene, shows up to help. He will easily dispatch the helicopters, leaving you with a few low level D.U.P. agents to clean up on the platform.
When you finally reach the roof, do your best to defend Fetch while she users her Neon powers to cut through the panels. When she's softened them up a bit, smash through to begin the final boss battle with Augustine.
The final boss fight plays out exactly the same way regardless of whether you choose Good Karma or Evil Karma. The only difference being the cut scenes as you progress. Since we're not about to spoil the story for you, we're simply going to link you to the final boss battle, which we covered in our Good Karma play through as well.
When Augustine finally falls, the game is over and you've completed the Evil Karma play through.