First off, the first encounter with the Dark Brotherhood, is either through assassins being sent for the player, or being captured by Astrid and told to kill at least one of three possible targets who have been bound and gagged for the Dark Brotherhood. As the player, we are expected to follow the path set out for us by the game in order to
Unlike the Shadowmere present in Oblivion, Shadowmere in Skyrim is not marked as Essential and can die, killing Shadowmere works for making it stop following you temporarily. However, 15-20 days later, Shadowmere will respawn in the location of death, causing it to start following you again. Shadowmere just seems invunerable, as it heals at the
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