This one starts immediately after Heaven Sent: Beam With Pride. Expect to be ambushed on your way to the starting point, but keep in mind that you're back in the open streets, and alarm levels do apply.
Hit the start marker when ready to get a bit of cartoon action, and access to the Scorpion truck. You'll get an initial objective that promptly goes out the window once meteorites start raining down on the city.
Drive around until the exposition plays out (and be careful about wandering into optional missions), then follow your marker to a construction site with a giant hole punched in it.
Jump up inside and scan for the first impact site- it should be right at your feet.
Use your locator to scan the other two fragments- they're both at this site, and each one requires going up a level. Scanning the third triggers your next mission- to take out a LEGION vehicle.
Return to the Scorpion and chase down the enemy truck. This may require a little adjustment- the Scorpion is just a little less agile than the vehicle you're chasing, and lot less agile than the Hammerhead you're used to driving- it can be easy to miss your mark when the truck takes a sudden turn. If you have trouble, focus on minor knock and sideswipes while in the open city, saving your big attacks for tunnels and straightaways.
Take out a second truck the same way, then follow your marker to a LEGION lair. The entrance is on the upper level, via a balcony facing the river.
Take out two waves of Swarmtroopers, then wait for the bossy-type fighter to appear.
He's got shields, but if you've been doing the character recruitment missions, you've likely faced tougher Shocktroopers than this. If he doesn't go down immediately, use the planter boxes to keep him at bay and take him apart. When he's dead, use your locator to identify the Lair access- a kiosk near the entrance.
The base itself is pretty standard fare. The first challenge is another destroy-LEGION-equipment-until-the-damage-bar-fills room, while troopers attack. Just keep moving and keep firing.
The next challenge is the LEGION commander - another shocktrooper in this case.
As ever, Fortune's pistols are great for blasting apart shields before they can regenerate. In general, use your threejumps and dashes to maintain distance and evade his attacks. There's also a health generator here if you need it.
Your next goal is a panel hack, but the room is filled with both enemies and traps. Take out the former and simply step around the latter, to hack in peace.
Snag the loot box in the next room, and activate the crates to start a series of ambushes. This is a good fight to deploy traps of your own, as the enemies arrive in clumps through actual doors and elevator hatches, rather than just teleporting in. Expect a wave of helltroopers, then blitztroopers, then helltroopers again, then blitztroopers again, then more helltroopers, capped by a blitztrooper commander.
With the enemy routed, activate the elevators and head outside. Exit back through the balcony and round the corner to load up the stolen crates.
You have to drive them to the rendezvous point, but it's actually a really short drive, and there are no ambushes. Drop them off to complete the mission.
You'll get the usual cash, xp & gadgets, plus you'll unlock the Scorpion for permanent use.