Looks like all those protesters on the streets have a mandate to keep it going . <| sep |> I dont know much about Supernatural , but i do know a shit ton about crossovers . You have a few potential beginnings and plotlines you could go for . 1 Supernatural characters sent to the futurefrozen in time . This would primarily be for if you want a character to interact with the Normandy crew , Main issue for this are things like why would the character be brought aboard andor how can they defend themselves in the situations Mass Effect has . 2 The universe has multiple issues of supernatural origins , ShepardSupernatural character has to deal with this . Not as easy to do as you have to write an entire universes superstitions , give reason for appropriate character to interact with this scenario , and make their actions relevant to the universe as a whole . This issue is compounded by the idea that if GodsDeities exist as per Supernatural , the reapers would likely be a non issue . 3 Shepard travels back in time . Simple but at the same time could easily lead to nowhere , Shepard uses Biotics to shield themselves during the crucible or other applicable event , Biotics destabilise into a time anomaly and shepard is sent to the past . Problems with this path are giving shepard a reason to work with the supernatural crew , a reason to believe when in many cases they are an agnostic . Having shepard not outshine the supernatural crew via mass effect tech . Those are the primary 3 ways i can see a SupernaturalMass Effect crossover going . Goodluck , this aint gonna be easy .