Consumed by Nightmare

I suspect the nightmares might be:

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• "Eaten" by Iso'rath.
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• "Dying" in the stomach.
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• "Dying" to Deathwing.
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Nightmarishly horrific ways for your life to end... and since Iso'rath manipulates our perception of reality, how can we know exactly what happened? Which were the nightmares and which reality? What if we never fell into its Maw and that was just a trick to shake our resolve?

This achievement is awarded after you escape Iso'rath's Maw, even if you only saw one nightmare with Thrall and Deathwing (don't know if there's any more)

What if we never fell into its Maw and that was just a trick to shake our resolve?

I came to WoWhead for the sole reason to find out what were "the other 2 nightmares except the Thrall one" and yeah it just seems "kill stuff" doesn't scare our protagonist any more so a poor choice of nightmares those were...

I'd make a wild guess one of them was "dying" to the slimes and waking up in the Thrall nightmare and then the last one was to free the fellow Shamans from tentacles?

Yeah I think the Thrall nightmare is noticeable because we can't fight to defend ourselves, can't do anything, so it's a nightmare indeed.