(Message from KAM about the new Reforms!)
Media was one of a few factions in the mod that had a unique roster but did not have any reforms, still resembling an Achaemenid-like army composition. Unfortunately, little is known of the kingdom itself. At first allied with the Diadochi, it quickly broke off, being either independent or a vassal state of neighbouring powers. At one point, Kings of Media were also granted the royal title and lands of Armenia.

Researching Media was a bit difficult on its own so I focused more on overall changes going through local cultures. This brings us to new unique features for this kingdom, their custom reforms. Late Achaemenid cavalry shifted more into the role of heavy mounted skirmishers. This soon started to drop after the conquest of Alexander the Great and the influence of Nomadic tribes. Horse armour became more and more heavy while bow and lance were now weapons of choice. Greek influence seemed to be small but we have evidence that even Parthians adopted thureos shields for their infantry. If that change was their native unit or some auxiliary force is not clear. 

For a late reform I went with a sort of proto-Sassanid theme. Due to the speculative nature of this, we decided to postpone it to the very late game. A historical Sassanid revolt against the Parthians started in Parsa, with Media eventually being integrated into the new state. Both rulers of Parsa and Media claimed to be descendants of the Achaemenid dynasty. As a player, your goal is to bring back the glory of the old Persian empire and unite long lost lands. In order to trigger the final reform, you need to conquer Nisa, Persepolis and Seleukia (future Ctesiphon) and have a minimum of 200 turns passed. Once reached, the army goes through large changes, both for foot and cavalry units. One of the interesting things I was able to find was that eastern cataphracts were also using cuirasses on top of their armour, rather than typical depiction of them, wearing just mail or scale. 

Iranian reform:
First of two reforms. Inspired by Nomadic and Greek armies, it brings back bows as a weapon of choice for light and medium cavalry. Nobles adopt early cataphract armour and deadly kontus lances, ready to break any opponent previously weakened by ranged fire. In terms of infantry, Thureophoroi are present in the form of a unit made mostly of lightly armoured Medians with Greek mercenaries being the best equipped soldiers in regiment. 

1. Grivpanvar – Early Cataphracts

2. Aswaran-i Madaen – reformed Median cavalry

3. Atropatene Thureophoroi – Median Thureos swords

4. Shivatîr – Horse Archers

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Imperial reform:
The last reform and with the largest amount of changes. While only available in the very late game, the unit quality justifies it. Fearsome Daylamites will be a tough opponent to any enemy of Media while super heavy Grivpanvar will rider over any opposition. 

1. Gond-i Shahanshah – Dylamite Heavy Infantry

2. Kamandaran-i Shahanshah – Royal Archers

3. Aswaran – Late Noble Cavalry

4. Dehqan – Late Medium Cavalry

5. Grivpanvar – Late Cataphracts

New standard:

References:

Additional sources:
P. Skupniewicz – Sassanian Horse Armor
http://www.iranicaonline.org/articles/army-i?fbclid=IwAR3t0myEdoXXWBKGCbW6A4fzbk6J2ClJloP2Wksxa30bdQ3UvI6GYoH9gMI
http://www.iranicaonline.org/articles/babak-2-6th-cent?fbclid=IwAR0_JrAHd2iaXULxxIfMDW9qLCF4G72JA5NPPO8UO8aV8uhaEFUnjGYr8EU

Credits:
Dresden for creating new reforms and help with unit setup
Jake Armitage for creating unit cards and new faction logo