How to unlock: Listen to Bain Massani's message [Eos].
Here you can find the guide for Kett's Bane quest. This is one of the Heleus Assignments (side quests) in Mass Effect: Andromeda game. This quest can be started after Eos has been terraformed. During it you must meet with the mysterious Bain Massani. He has information that can be useful in weakening the Kett that are on Eos.
Unlocking the quest
This quest becomes available after Eos has been terraformed. This means that you can now explore the west part of the map without the danger in the form of deadly radiation. You should receive a message through radio from Bain Massani. After that the marker, presented in the picture above, should appear on your map. Bain wants to meet with you and talk about weakening the Kett on Eos.
Meet with Bain
Your target destination is Kett's bunker and when you get there you must defeat a group of enemies. After the fight go inside the building and speak with Bain Massani. He gives you the locations of Kett constructions.
Destroy the generator
A Fiend is near the generator. You can defeat this enormous beast in a regular fight (use ammo and powers that weaken the armor bar) or lure it into the buildings. Regardless of your choice you can now sabotage the console inside the building.
Destroy the barracks
The barracks are on a small hill and in order to complete this mission objective you must eliminate all Kett that are nearby (additionally, you can listen to audio log but this is optional).
Securing both locations completes this short and easy quest.
Rewards for finishing the quest: XP, Andromeda Viability Points.