AH Challenge: Zoroastrian Tabarestan

Here's a little idea I had for a challenge: have the region of Tabarestan (roughly the Iranian Caspian coastal area) survive with a fairly strong Zoroastrian majority until the Mongol invasion.

Some historical background: Tabarestan was the last part of Persia to be conquered by the Arabs, and it remained independant for roughly two centuries after the rest of Persia had already become a part of the Caliphate.

Furthermore, even after Tabarestan became part of a muslim state, it became part of an early Zaydi state, and because the Zaydi's are a Shi'ite sect, the influence of the Caliphate was never really strong in this period.

And this state soon fell apart, after which Tabarestan became controlled by the Ziyarid dynasty, that controlled the region until it was conquered by the Seljuks between 1040 and 1042. But Tabarestan had already been weakened and reduced to a tributary state of the Ghaznawids somewhere between 1010 and 1020.

Nonetheless, in spite of the (at least nominal) muslim rulers of the Ziyarid dynasty, the majority of the population of Tabarestan remained Zoroastrian until the 12th century.

..
Now then, here's the actual challenge:

10 points for having a Zoroastrian majority in Tabarestan when the Mongols invade. (required)
15 points for having the Ziyarids rule Tabarestan when the Mongols invade.
20 points for having a Zoroastrian renaissance during the Mongol age (including conversions to Zoroastrianism, Persian nationalism, etc.)
25 points for having Zoroastrian Tabarestan becoming a semi-independant principality under Mongol overlordship
30 points for having a Zoroastrian majority here surviving long after the Mongols are gone (at least one century)
35 points for a more or less independant Zoroastrian Tabarestan (in a way comparable to Armenia; sometimes occupied, but nonetheless surviving)
40 points for a significant Zoroastrian revival throughout Persia under Mongol rule

...and then the two bonus challenges:
50 points for a Mongol Il-Khan becoming Zoroastrian
100 points for a scenario in which Zoroastrianism becomes a large or even major religion again.
 
very sorry to bump this thread, but A) I hate it when threads get no replies
and B) I found a possible solution. Mardavij, the founder of Tabarestan, was suspected of actually being a Zoroastrian.

quoth wikipedia:

"
He expressed his wishes to see a return to the Empire of the Persians and Zoroastrianism, after ousting the Arabs and Islam."

so maybe he goes to Tabarestan, finds some allies (Byzantines, Khazars, maybe the Karluks or other pagan Turks) and they all agree to gang up on Persia and crush the Abbasids and Samanids. Somehow their plan succeeds, and Mardavij declares himself King of Persia, banning Islam and making Zoroastrianism the state religion once again. over time the Arabs and Muslims are driven out or converted, so by the 1200s Persia is Zoroastrian again. but then the Mongols come along and smash the Ziyarid Dynasty and conquer Persia. following the break-up of the empire, the Il-Khans convert to Zoroastrianism (as they did to Islam IOTL).

how's that?
 
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