Leman Stark

The MC gets the chance to go again and chooses to go to the world of ASOIAF/GOT but with the powers and abilities of Leman Russ from Warhammer 40k. He chooses to take the position of an OC Stark and change the sad and stupid fate of House Stark. What could go wrong when House Stark gains a Primarch-level powerhouse ... nothing right? ... right? Well, not for House Stark at least. This is a wish fulfilment and yes, the MC is pretty much OP from the get-go, but hey, that's the premise of the story. It can still be interesting ... I hope. No harem, single FML and I bet you won't know who it is.