Missing expedition

The Serviceman's PDA was the only potential information on the location of the missing expedition, but Barkeep's technicians broke it. You stumble upon an unexpected lead in Army Warehouses.
== Walkthrough ==
=== Ara ===
In Deal with the whistler, you will encounter and kill Pavlik's mercenary contact, Ara. His flash drive contains the information on a group of scientists that went to the Radar's Rusty Forest and never returned, and that his commander, Ashen, knows more on that.
=== Joker ===
The next is what is one of the most over-the-top fights in this game. You'd better be prepared by taking a lot of pistol ammo and a sniper rifle, or at least take about 300 5.56x45 rounds and use the LR-300 "Sniper" that can be found in a breakable box on the bus stop in the outpost.
Visit the [ mercenary outpost] at Army Warehouses, and wipe 4 mercs there. Listen for the group leader Joker screaming for reinforcements at his superior Ashen over radio.
The reinforcements actually arrive in several seconds, in the form of 103 mercenaries, one of which is Joker himself. The mercenaries spawn over a wide area (see the picture) and keep slowly coming to the outpost as long as they see you, over the course of a couple ingame hours. They spawn in 6 waves, some of which are beyond the online radius, so you'll only see them if you move out of the area.
On Joker's body, you can find his PDA with the transition between Army Warehouses and Wild Territory.
=== James ===
James is the merc who took the suitcase from Freeman in Mercenaries' suitcase. You have to deal with him and return the suitcase to Freeman to continue this quest.
=== Ashen ===
Warning: if you completed Mercenaries' suitcase and Deal with the whistler, but haven't fought Joker yet, go and do that now. Otherwise you'll miss Joker entirely, and the transition from Army Warehouses to Wild Territory will be lost as well.
After dealing with Ara and James, Ashen with the rest of his mercenaries will spawn on Wild Territory, at the [ road to Yantar]. The fight here is very similar to Mercenaries' suitcase#Aggressive option, except it "only" involves 64 mercs slowly spawning for a real life hour (including one with M60), and a teleport blocking your way out until you read Ashen's PDA.
Ashen's PDA contains the rest of the story - that a small merc squad followed a team of 15-20 scientists into the Rusty Forest on Radar, killed several of them, and stopped the pursuit as they were too close to the Brain Scorcher.
=== Sakharov ===
The dialogue with Sakharov will be available after the "Search for Ghost" questline (specifically, you should accept the Ghostly hope from Yakut).
Upon questioning, Sakharov will recall that there was a scientific expedition planned into X-10, but it was never heard about since they departed.
Bug warning: Do not interrupt the second to last dialogue from Sakharov when talking to him, otherwise, the dialogue will disappear, never allowing you to complete the original Missing expedition. After talking to Sakharov, double check that you have just one and not two duplicate tasks called "Missing expedition" in your PDA!
=== Missing expedition in X-10 ===
After entering X-10, you will discover bodies of scientists and their military escort, which is the remains of the missing expedition. One of the scientists, Erofeyev, seems to be still alive but badly wounded. You can talk to him, and he will say that bloodsuckers left him for later, but he will die on the spot anyway. After the talk, 8 bloodsuckers will spawn.
Ghost will send you a message, saying he has things to discuss with you. This unlocks his quests after Trap for Beast II.
== Notes ==
* This quest triggers immediately after A nasty accident, even if you haven't recovered the flash drive from Ara's body. This is probably an oversight since Marked One had no way to know to search for some merc before he stumbled upon Ara's note.
* You don't need this quest in your PDA to meet and kill Ara and Joker; you can get the quest later.
* The ammo crates on the outpost are bugged; if you hide behind them, you'll become invisible for AI and can wait for them to come closer to shoot them with a pistol. This is a good spot to advance Test of pistols.
* Make sure to actually wipe every merc out, don't run away from this fight. They won't despawn and will keep harassing everyone in the area, especially you.
* Joker's ambush can also be cheesed by immediately running from the outpost. Mercenaries can be baited into fighting invulnerable NPCs such as Wolf, Yakut, and Kostya in the [ Loners' camp], and Morose in the [ bloodsucker village].
* Ashen actually spawns very early in the waves in Wild Territory, on the Yantar side of the Burner tunnel. If you're quick, you can grab his PDA to disable the teleport and head back to a more advantageous position.
** When heading to the Bar side of the tunnel, you will need to fight through several mercenaries on the way there. After you get through them, the encounter is much easier due to the pincer being negated.
* Joker's PDA isn't needed anymore, you can give it to Sviblov for his "one-time cyclic" quest.
* The breakable box with the LR-300ML "Sniper" at the mercenary outpost is instantly deleted upon Ashen's death. If you want it, make sure you grabbed it before that.
* The bodies of the scientists that were killed by Ashen's squad can actually be found at Radar.
== Bugs ==
* Technically, this quest consists of two quests with the identical name (before and after speaking to Sakharov). Don't ever interrupt the dialogue with Sakharov mid-talk, finish it properly. Otherwise you can miss some internal trigger and end up with the first task stuck in your PDA forever.