Cephalon Samodeus is the Cephalon thought to be responsible for creating all Mods (including Riven Mods) within the game. He also seems to be the one responsible to occasionally adjust the dispositions for every Riven Mod.

"Until now, you've ignorantly used my creations for whatever suits you, but this is only a taste of what I have accomplished. For now, you can nest my beautiful creations inside your crude rifle like a sad philistine until you understand the depths of my unique creations."