Mission and Clear Conditions:
Rescue Hostage (Side Route, Red Zone)
Capture Heavy Heliport (Main Route, Yellow Zone)
1 Combat Echelon Level 90 5x Linked. RF/HG Recommended for Capturing the Heavy Heliport, but AR/SMG can work just fine.
Combat Missions in Chapter 3 start off fairly simple, while also introducing yet more new enemies, this time, ELID Infected.
ELID are present in two variants here, Ranges, and Melee. The Ranged ELID function much like a Strelet, Ripper or Cyclops, while Melee ELIDs are similar to SF Guards. For the most part these enemies pose a threat only due to their sheer numbers, not so much their combat abilities.
The far right of the map features some KCCO units including a Hydra, making the Heavy Heliport capture objective require either RFs or a specialized and heavy-hitting AR Echelon.
Deploy a Combat Echelon on the Command post. Move up to rescue AN94, and then follow the left path to the Heliport, and end your turn.
Heavy Heliport Capture
Deploy an Anti-Armor Echelon on the Command Post, and move up to rescue AN94. From there, move right two nodes, up one node, right one node, and up a final time. This is a bit of an odd movement pattern, but it has a chance to reduce the number of fights required by one, reducing chip damage, and saving a few resources.
Move your Echelon down, right twice, and then down twice. You will have 1 AP remaining, but should end your turn now.
End your Turn, do not move. This allows 416 to destroy the other Mortar, and SOPMOD to kill a pair of KCCO units. While not a requirement, this removes any need to worry about ammo or rations, or having to futz with retreating from Mortar shots.
Now that both Mortars are out of commision, and SOPMOD cleared a few of the KCCO out, you can follow the path up-right four nodes, right ,and then onto the Heavy Heliport. Be advised there is a Hydra on the Heavy Heliport, which may require some micro to destroy.