The Strong Survive
Once you're out in the city, attack the Blackwatch Commander as instructed. Consume him then escape the red-alert area. Just keep holding R2 to sprint and Heller will do the scaling and jumping automatically. After breaking Blackwatch's line of sight, change to your other form.
Consume some civilians to boost your HP then head to the building marked in your map. Scale the wall and step on the blue marker to check the area. Head to the church next and air glide to reach it quicker. Approach the marker for a scene.
Head to the hospital rooftop and step on the blue marker to acquire your Hunting Ability. Press L3 to hunt the commander. Once you have acquired the target just glide to his position and consume him immediately. Escape the alert by killing all the guards and shapeshifting to your other form.
Once done, jump to the ground and step on the marker. Send out a hunting pulse as instructed, then go to higher ground. Send out another hunting pulse and take note of the direction of the return pulse. Rotate your camera to the direction of the pulse then send out another pulse to determine your target's exact location. Your target should be in the middle of the return pulse.
Spring, jump then glide to cross the broken bridge and find your next target. Consume him then escape the alert afterward to complete this mission.
From hereon you'll be in free roam. I suggest taking this time to find and locate all collectibles in the current zone you're in as they'll help unlock new skills and abilities needed to improve your chances against Blackwatch. For the exact locations of the collectibles, please refer to the collectibles section of this guide.
For now, you can collect all Blackboxes and destroy all Field Ops to get some new mutations. There's a lair in Linden Park but you can't destroy it at the moment so ignore it for now. Once ready, head to the next mission marker to start the mission.