I remember doc scratch saying something about Eridan like he was nihilist but not in the "cool way" in the really sad way and implying he'd been influenced or something???? Was doc scratch controlling Eridan did I miss that somehow. I mean I know he conditioned their whole race towards violence but is it something more than that

He just said he was on the ‘path to nihilism’ in the conversation with Rose where he implied Magic wasn’t real and all of their powers were innate. Nothing about being controlled as far as I can tell.