Taliesin (portrayed by Karl Johnson) was a seer over three centuries before the events of the show. Using the mysteries of the Crystal Cave, he was able to see the future in great depth. Although he died years ago, he appeared to Merlin- it was unspecified whether Taliesin had left a magical 'recording' of himself to pass on his message, had come forward in time from the past, or if this was merely his ghost- when Arthur was badly injured by an arrow, healing Arthur's wound and subsequently taking Merlin- whom he referred to as 'Emrys'- to the Crystal Cave, where he showed Merlin the crystals, explaining that only a few rare individuals are able to use the crystals to see the future. He claimed to have seen visions of Merlin during his lifetime, hinting at Merlin's great destiny in the future.
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