|Alpha will now be joining you, Nero, Midgardsormr, and Cid on your return. Give the first Level Checker a whack and Cid will get to work on the barrier. Alpha will charge forward... into a trap. The three of you that remain will need to deal with the adds, a pair of Sigmascape Roaders. Once taken care of the barrier will fall and Alpha will be freed, allowing you to proceed.
You'll arrive with Alpha and Midgardsormr without your garlean companions. You'll need to face three more Sigmascape Roaders more or less by yourself, your two companions just auto-attacking. After a while three Sigmascape Koja will appear and join in the fight. Once they're down, even more add boxes will drop down, but Alpha will use Dispel Card to take out all the Level Checkers at once. As the boxes prepare to open a cutscene will play, and your other two companions will join you, Nero now in his armor and armed with his magitek hammer.
The fight will be against three Roaders and three Koja. Gather them all up and AoE them near Nero, who will occasionally use his own AoE Mighty Overdrive. More boxes will drop during the fight, just deal with them the same as the first batch. Once they're all done you'll head to the next section, Alpha will use Dispel Card on another horde of level checkers, and Nero and you will mop up the four adds.
At the final platform you'll encounter Dadaluma. He'll hit pretty hard, especially with Explosive Fists and his dodgeable Aura Cannon, but Nero will ready his Mighty Shatter shortly into the fight and knock off a good 30% of his HP. Just keep up the pressure and he should fall before too long.