Worshipper – “Agral’s Decision” [Campaign 2, Mission 5]

I immediately stumbled upon an island, crossed the bridge, defeated the dragons, saw a cave, and there was a druid on it. But the cursor shows a crossed-out red circle (no moves left). I think it's just a decoration, so I reveal the entire map. Realizing that this druid is my target, I return to the island with the sitting druid. I move the cursor to the druid, then to the entrance of the cave – a red, crossed-out circle appears.
What should I do?
Version 1.6
Difficulty: Hard
Thank you.