during the quest to kill the Emperor. How can I get him back? I can't fast travel at the moment.

If you summoned Lucien Lachance he's gone forever.

If he died he'll respawn at the location of his death in 10? game days (maybe 30).

If he ran off he'll appear when you Fast Travel...when you can.

I summoned Lucien before I got Shadowmere. I fast traveled to Solitude to poison the Emperor. Then, that is when I lost him. I couldn't just go around the front to get him or I would have been killed. Is it possible that he is still at the stables in Solitude?

That's where my horse was during that quest so yeah go check.

I had to slay 5-10 guards but once I got my horse I hauled ass out of there.

I've never had a problem with Lucien and Shadowmere, but I did just have my first experience of Shadowmere simply vanishing. I have been in a hurry equipping the citizenry with new weapons, and I fast traveled to Skyhaven (on my way to Old Hroldan) just to check Delphine is still missing her Blades armour (she was ) and because I arrived inside Shadowmere was completely gone. I should have checked with the console just where he was, but I was in a hurry, and he did show up the next time I fast traveled.

If you're on PC there's commands for everything from going to him, bringing him to you, or making a copy of him. He often inexplicably runs off almost beyond my rendering distance in my game and then will just stand there forever (presumably) if I don't go fetch him. I always hunt for him with the Aura Whisper shout when this happens.

Edit: I'll be glad when I finally finish running all over Skyrim reverse pickpocketing the NPCs, and then Shadowmere can go back to just hanging out in the Riften stable.

So let me get this straight. I can't use both Shadowmere and the Conjuration spell I got from the brotherhood? I have to pick one or the other?

I can use both, but some people have reported trouble with it. Lucien talks to Shadowmere, so they are obviously supposed to both be available to the player at the same time.

Last I checked it wasn't confirmed, but there seems to be a high correlation. Don't be fooled by the Vampire Lady...that's what they do.

Hmmm.......interesting. I was curious. Does Shadowmere have a hightened toloerance to taking damage than the normal horses?

Kinda'. He's level 50, but his apparent "tolerance" is due to his crazy Health Regen rate. If you ever get to see it go up it's unbelievably fast.

Good stuff! I found him. He was waiting for me at the stables in Solitude.

Sweet. I would be so pissed if I lost him - it's why I won't summon Lucien.