During first playthrough, the player reaches a friendly who proivdes two swords. Afterward, the player exits onto a big stone hand to face Dax with the objective "Break Dax's block 1 time".
I could not break Dax's block with the heavy attack, for some reason. Instead, I used the Jump-slide combo to knock Dax down and kill it. With Dax despawned, the objective to break its block remains. No apparent way to progress without maybe? restarting.