After completing Kree-Search and Development, follow your marker to an Attilan door guarded by Sentry 459.
His beam is highly damaging, so avoid it while he's firing, and attack him when he's not. He also reacts badly to melee attacks, so pinging him from a distance will do. You can use the balustrades here for cover, while waiting for your chance to counterattack.
Likewise, when goons attack, deal with them down in the street or off to the side- anywhere outside the Sentry's firing range. As you continue to do damage, the sentry will start summoning healing drones to restore health. Destroy these as quickly as possible, then resume your barrage against the sentry itself.
Keep it up until he falls, then enter the door behind him to begin the mission proper.
A cutscene plays and you'll find yourself trapped in a junkyard. As per standard-ops, smash everything. Then use Triton to investigate the Clue marker stage left.
Follow the trail to some parts which can be used for one of Lockjaw's doggy dish teleporters.
Activate it as Lockjaw, then pull open the Hulk Handled door to let the rest of the team through.
Wipe out the Kree goons, and smash everything on the ground level. One of these smashables is a Lockjaw statue, underneath the rightmost monitor screen.
When things have quieted down, use Crystal to power up the electro port stage left, by your entry door and the giant tank.
This create a spiral staircase up to the stop. Use Crystal's fire beam to melt the bricks holding the ice-turrets, then set your people on the pressure plates. This can be a little tricky, as the slow drip of incoming goons will occasionally knock one figure or another off the edge, but you'll get there with patience.
Activating all four opens the tank for Triton to dive down and activate the button (the giant fish here is not hostile).
This opens roof latch and lowers a little portable room. For the moment, however, fly straight up from the tank as Black Bolt. There's a Lockjaw statue here, and Stan Lee in the corner. Destroy the non-humans drone around Stan to free him.
Fly over to the green room that just appeared, and use Blackagar's sonic attack to shatter the glass of the Sentry's body.
Use the debris to make a door console. Number whirr and spin in the readout- ignore them. Instead, press the direction shown by the arrows when they appear.
Getting all three opens the nearby door, revealing a sliding floor, and another Lockjaw statue.
Smash everything in the room, and use the bits to repair the floor. This will allow you to slide teh blue and gray doohickey into place.
Once slotted, its laser reveals a button on the wall, use the newly revealed springboard to reach it.
This opens a clamp, lets in some kill-droids, and activates the buzzsaw on the wall stage right.
Kill the kill-droids. Now's also a good time to snag the final Lockjaw statue- the teleporter to it is downstage and center, if you've cleared all the junk away.
Smash everything. Smashing the last statue gives you one minikit, but there's another hidden inside the yellow box here to plunder.
When you've cleared the space completely, 'port back up the use Triton's spear on the port by the saw.
Swing back and forth across the blade's path (after it's gone by, naturally), then up to the bars on the wall.
Jump over to the high platform, and investigate the Clue here, then follow the trail.
Build a spear-switch with the pieces you uncover, then throw a spear in it. This unlocks a laser passage.
It looks harder than it is- just fly in over the topmost horizontal beam, and focus on evading the two verticals.
At the other end, grab the minikit up top, then hit the switch.
Gather everyone on the elevator for a final confrontation.
Ignore the pressure plates and inert gold-vest droids for now. The weak point of Maxie's mech is the legs, which have little pull-loops on them. Use Medusa to snag these, and pull the joint apart.
This leaves him vulnerable to regular attacks – for a while.
Repeat until he raises a special shield. Step on each of the two pressures plates (doesn't have to be at the same time) to neutralize this protection.
This also activates the gold-bots, who can be melted by Crystal.
Kill them, and beat down Maximus for him to unleash one last trick. First, you have to skydive through his laser net (as before, this is easier than it looks, just don't oversteer).
Once on the ground, just use B-Bolt's sonic attack to smash Maximus' shell and end the mission.