Beard's backpack

Beard stashed Phobos somewhere in the [ Jupiter plant], in the vicinity of the staircase.
This is a timed mission. After accepting it, make sure to follow Beard's instructions.
== Walkthrough ==
=== Getting to the backpack ===
The staircase Beard is talking about is shown on the picture below. You can enter it from inside the administrative building.
As you start rising up the staircase, a huge amount of Monolith spawns above and below, trapping you inside. Additionally, several helicopters fly in. Ignore those below, kill three of them above, and make your way to the top of the staircase, hitting the locked grate.
Marked One contacts Beard, and he tells you to continue climbing upward. Follow his advice immediately to not be swarmed by Monolith:
After downing 9 helicopters in this small space you have left, 15 (!) more BTRs appear below. You'll have to blow them all up. In the following message exchange, Beard says that he apparently hid the backpack on the roof, starting the task Way to the roof.
=== On the roof ===
After getting to the roof, pick up Beard's backpack which is not hidden in any way.
Beard messages and tells you to stand under the antenna under which you grabbed the backpack, as Docent reprogrammed it to cover you from Monolith helicopters.
Shorty after entering the spot under the antenna, you hear the helicopters coming in; Shadow of the Monolith arrives and wants to talk. He wants to invite you to an event, and marks the place on your PDA map.
=== Monolith parade ===
Note: after this event, Monolith will turn neutral towards you. Your reputation with them will be set to 300. You may want to complete Mystery of the islands and specifically Liberation of the Slavik the Bullfinch's squad before starting this event.
The place is nearby; just stand in the marked spot and watch the cutscene of massive amount of Monolith forces arriving to honor you. Shadow will also arrive. Talk to him. He seems to realize that he's unable to defeat you, and offers neutrality.
Watch the Monolith leaving, and pick up your armor and weapons taken from you during the cutscene. They're under the bush nearby.
== Notes ==
* Once the Monolith ambush has started, trying to descend the staircase will fail the mission.
* Three helicopters will come per wave, making a non-tracking strafing run across three angles aimed at where you were when they spawned in. You can bait the targeting by standing on one side of the staircases and moving to the other side when the salvo begins.
** If you move enough along the z-axis none will hit you, but be careful not to go in range of a BTR later on. Low crouching also seems to help.
* Any helicopters left alive after their initial strafing run will make another after you are in view for long enough, adding pressure to take them out immediately.
** The helicopter to your front is always the highest priority due to very little cover from that angle.
*BTRs seem to be unable to shoot you through the staircase railing similarly to how they cannot shoot you through bushes.
* Not all BTRs are visible immediately; beware of two to the west that are semi-hidden behind the building corner.
*After the parade, your reputation with Monolith forces will be locked at 300 until the middle of Chess Player. Even killing Monolith forces will not lower it, though it will cause the rest of their squad to attack you if their attitude is lowered enough.
**Passing through Monolith-controlled zones like Radar or Central Pripyat will become significantly smoother. You'll be free to explore these areas without fear of harassment.
**Late game quests like Old friend will be much easier to take on during this truce. If you're still after Monolithian loot, you can simply initiate combat from an advantageous position and the rest of the squad will aggro as normal.
*Don't try to be cheeky and lay landmines along the parade path. All of the Monolithians in this event are entirely invulnerable.
* During the parade, more than 80 Monolithians come out of a single BTR dropped from a helicopter, and then board it again.
== Bugs ==
* Do not jump while crawling up the tiny opening in the staircase as you can become irreversibly stuck.
* Sometimes dialogue will advance before all of the vehicles have been destroyed. No adverse effects seem to occur if this happens, but make sure to destroy all helicopters and BTRs regardless.