<p>In the begiining of the episode you can see Brienne and behind her are knights/soldiers bearing shields with the Arryn sigil, so the Vale Knights were there, but commanded by Brienne, not Yohn Royce. Maybe his absence will be explained in the next episode.</p><p>(Usually, when a character in a series is suddenly absent, I say 'he is fetching the mail'. This comes from an anecdote from the cowboy-series Rawhide. There were a few episodes where Clint Eastwood's character Rowdy Yates was absent, and the saying was that 'he was fetching the mail' in whatever town they were near).</p><p>
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