Probably my first "God tier" riven mod that I rolled : r/Warframe
I made a riven calculator that tells you the probability (and kuva cost) of getting your desired roll. Fully customizable and easy to use! : r/Warframe
Dragonblade Riven by cyblix on DeviantArt, dragonblade riven - thirstymag.com
Riven Price Calculator for Warframe - Warframe Data