1. Four years ago today three hit teams killed 130 people in Paris, the most significant ISIS attack so far, but their instructor is still shrouded in secrecy.
A Swiss-German convert, Thomas-Marcel Christen rose to the very top in ISIS external operations. https://www.bild.de/bild-plus/politik/ausland/politik-ausland/is-anschlaege-in-paris-das-ist-europas-gefaehrlichster-terror-planer-65987522,la=de.bild.html

2. A Swiss national from Aargau, Christen's parents divorced when he was a child. He lived with his father at a campsite in France for several months in 1998 before his mother took him back to Switzerland and then moved with him to Frankfurt in 2006.

3. TMC often visited Frankfurt's Abu Bakr mosque where he converted to Islam in 2009. It was likely here that he met radical Moroccan-German preacher Said Emrani aka Abu Dujana for the first time, whose sermons influenced him back then.

4. After moving to Bonn, TMC married a close relative of Abu Dujana with whom he had a daughter. In March 2013, he travelled from Cologne to Paris and then to Istanbul. TMC took with him cellphones, laptops and 15,000 Euro.
In July 2013, his mother heard from him the last time.

5. Christen, who was now called Abu Musab al-Almani, quickly rose within ISIS ranks. As early as 2014, he was already head of the Amniyat unit in Manbij, back then an important transit town near the Turkish border.

6. This might be due to his commitment and his language skills: He was fluent in German, English, French, Arabic and reportedly also some Russian. He also had very strict OPSEC: Unlike other foreign fighters who posed with guns and black ISIS flags, TMC never posted such pics.

7. A German ISIS member said that TMC confiscated cellphones when he suspected that someone took a pic of him. He was also described as hot-tempered by a German ISIS member: TMC once raged after losing a game of chess. Two Germans thought of calming him down, but were too afraid.

8. At some point he got to know Abu Mohammed al-Adnani, ISIS' official spokesperson, a veteran of the organization since 2003 and one of it's very top leaders.
TMC reportedly married a close relative of al-Adnani. He now had personal ties to the core leadership of the group.

9. Al-Adnani was also head of ISIS Amniyat and it's external operations. While most ISIS attacks worldwide are executed by supporters who might have been instructed via messengers, ISIS also trained attackers in Syria for much more sophisticated attacks than with knives and cars.

10. As this network for terror attacks within ISIS can rather be defined by its members and their relations than institutions, Western intelligence agencies named this complex "OSEO":
Organizational Structure External Operations.

11. Thomas-Marcel Christen soon became a key player within OSEO.
He soon became Amir his own special unit Katiba Furqan which was based in Raqqa and had between 50 and 100 members whom he trained for terror attacks abroad.

12. TMC named his unit Katiba Furqan after the 25th surah "The Criterion", which says about the disbelievers "But they have denied the hour, and we have prepared for those who deny the hour a blaze."

13. On November 13th 2015, TMC's phantasy about a blaze became reality in Paris: On 0920pm a suicide bomber blew himself up outside the Stade de France during the FRA - GER match. Soon after, several ISIS hit teams attacked bars and cafés, killing people with military precision.

14. The hit teams were equipped with AK style assault rifles which they used in single fire mode, murdering their victims more efficiently than just by spray and pray. More than three dozen people were killed in bars, restaurants and open streets.

15. ISIS terrorists Foued Mohamed-Aggad, Ismaël Omar Mostefaï und Samy Amimour stormed the Bataclan hall where US band Eagles of Death Metal were playing a concert.
The attackers murdered 89 people with assault rifles and explosive devices.

16. 130 people were killed in Paris. The ringleader Abdelhamid Abaaoud managed to escape and was killed in a raid five days later. Salah Abdeslam, the lone survivor of the terrorist cell, escaped to Belgium where he joined the rest of the Paris-Brussels ISIS terror network.

17. The attack was the most significant ISIS OP 'til today. The French government declared a state of emergency, thousands of soldiers were deployed in the country. France enhanced it's anti-ISIS operations in Syria, the German Bundestag supported the mission with Recce Tornados.

18. Authorities were looking for planners behind Paris.
Soon names started making the round:
Boubaker Hakim, a French Amniyat member.
Fabien Clain, who spoke the audio claim for Paris.
Belgian Oussama Atar, whose kunya is Abu Ahmed al-Iraqi as he fought for the org since 2003.

19. But one name didn't show up: Thomas-Marcel Christen. Authorities knew his kunya Abu Musab al-Almani before, but weren't sure about the elusive person hiding behind it – who wasn't a German national, but a Swiss.
Who didn't allow pics of himself and broke contact w his family.

20. ISIS celebrated the Paris attacks with several videos from their provinces.
But on 24.01.16, their central video branch al-Hayat media – then lead by German Christian Emde – released a 17:39min video with new footage of the Paris attackers.

21. The footage shows the Paris attackers dressed in combat gear shooting and decapitating prisoners most likely somewhere in Syria. Among them were the Bataclan attackers Ismaël Omar Mostefaï, Foued Mohamed-Aggad and Samy Amimour.

22. But there is also one short sequence which shows one of the Paris attackers during a live fire exercise, probably on an abandoned military base in the vicinity of Raqqa/Tabqa.

23. This is Brahim Abdelslam aka Abu Qaqa al-Baljiki, who later shot people in bars and restaurants in Paris' 10th and 11th arrondissements and who finally blew himself up in the Comptoir Voltaire.

24. During the combat exercise, an instructor can briefly be seen pushing Abdselam during the shooting, to train him staying focused on his targets even in a panicked crowd.

25. The mysterious instructor is apparently wearing combat gear and a balaclava, but he was also pixelated by ISIS media to make his identification even harder.

26. The pixelated trainer we can see in this short sequence is indeed Thomas-Marcel Christen aka Abu Musab al-Almani, the elusive instructor of the Paris attackers.

27. A German ISIS member later told me that TMC spend hours on the shooting range himself everyday. "He was basically shooting all day, he would watch videos of Western SOF drills and then repeat it on the shooting range."

28. The significance of the Paris OP was also reflected in the way ISIS media exploited the attack. They released several videos from their provinces, articles in their magazines and then the big "Kill them wherever you find them" video, which was done like an action movie (18+).

29. Authorities meanwhile were zeroing in on the remaining members of the terror network, but on 22/03/16 the cell struck Belgium: Suicide bombers attacked Brussels airport and a metro station, killing 32.
At least two members of the cell were trained in Syria before.

30. After the Brussels attack, ISIS al-Hayat media released another video which includes the same sequence of Abdeslam during his training with TMC, but this time the Paris attacker can be heard speaking.

31. The video goes on showing the training sequence with TMC again, but then also showing scenes of the Brussels attack and the Brussels cell members Najim Laachraoui and Mohamed Belkaid who wear the same combat gear as the Paris attackers and were also instructed by Abu Musab.

32. The deadly attacks in Paris and Brussels were also a further career booster for the instructor Thomas-Marcel Christen within OSEO.
He was promoted and became the overall ISIS ExOps commander for the whole European theatre, subordinate only to Abu Mohammed al-Adnani.