The Great Silence:
Loco is pulling the outlaw behind him with a whip he got round the outlaws neck.
There is an extra rope attached to the saddle, because it would have been too heavy for Klaus Kinski to pull the man by just holding the whip.
The Rope is gone when we have a rear view.
And attached again in side view.
Something moving fast in the background (behind Silence), possible train but could also be video garbage or dirty lens.