As mentioned, the series features frequent and intense depictions of destruction. Mass killings are implied multiple times, though mostly mere aftermaths are shown, i.e. bloody bodies lying around, burning buildings etc.
The first episode's last third is particularly intense and conveys a heavy sense of danger and threat. Some might find the dragon in the first episode repulsive and disturbing.
Infrequent, but intense and surreal prophecy sequences: we see visions of massive destruction, death and distorted reality. In one such sequence the main character is standing on a field filled with bodies. Blood is raining from the sky, and we see a ghostly image of a support character who has been shot with multiple arrows sink slowly into a pond of blood.
One of the antagonists is clearly insane, sadistic, and takes joy in slaughter. His behavior and the reason behind his identity may be disturbing for some.
One scene shows a badly injured character screaming in agony and convulsing so hard he has to be tied down. In another scene it is implied his chest is about to burst.
Many of the character backstories are quite tragic, as many members of the cast have lost family, friends or both.
This series is fairly intense and features numerous and intense depictions of war and battle.