Hi all

Hoping y'all can help me. I'm looking for a specific fic where Cas was trapped in a Purgatory type place and Dean went after him. I remember Dean disguised himself somehow and teamed up with someone (maybe Gordon?) who led him to a settlement where Cas was tied to a post being tortured. The monsters kept making him manifest somehow and he was pretty far gone. Very animalistic. Dean breaks him loose but it takes time for Cas to even recognize Dean.

Does this sound familiar to anyone? There may have been a train (maybe metaphorical?) that they eventually escape on or I may be blending stories. Any help is greatly appreciated.