In the Shahnameh, Rostam and his predecessors are Marzbans of Sistan (present-day Iran and Afghanistan). Rostam is best known for his tragic fight with Esfandiyār, the other legendary Iranian hero; for his expedition to Mazandaran https://en.wikipedia.org/wiki/Rostam
HQ2+ equipment caps at Rank 25, for a total of 25150 Reinforcement Points to max out the item.
In order to earn Reinforcement Points, you have two methods. You can use a combination of both in order to earn points. You are not limited to one or the other.
Method #1 Trade the piece of equipment along with one of the following items in order to earn RP:
Heroism Crystal - Each Heroism Crystal is worth 10 RP each.
Heroism Aggregate - Each Heroism Aggregate is worth 50 RP each.
Method #2 Defeat foes within Dynamis - Divergence while equipped with the gear you wish to augment.
Wave 1 Monsters: Squadron Monsters are worth 10 RP each, while Leaders are worth 20 RP each.
Wave 2 Monsters: Regiment Monsters are worth 20 RP each, while Leaders are worth 40 RP each.
Wave 3 Monsters: Normal Volte Monsters are worth 30 RP each, while Volte Leaders are worth 50 RP each.
See the Dynamis Divergence Weapon Augments BG-WIKI page for a list of maximum augments for each weapon.