Kingdom

You can't watch one without the other, and you've got to watch the first season to make sense of the sequel.

And obviously, if you enjoyed the first season, you would expect closure in the second season. Again you would expect closure in the third season

Expect more of the same, with blood and guts galore.

Retaining the cast not only maintains the production standards but also preserves the continuity of the plot.

859 AD. The once-great Tang Dynasty is now declining. Numerous rebel groups have formed, the largest of which is the House of Flying Daggers, based in Feng Tian county. They steal from the rich and give to the poor, gaining the support of people. The local deputies have managed to kill their former leader, but the rebel group only becomes stronger, due to a mysterious new one. Jin and Liu, two police captains, are ordered to kill the new leader within ten days.

Both feature zombies, obviously, but they also show that, apart from a few heroic figures, bureaucracy and figures of authority are more interested in saving their ass*s and holding onto their power, instead of really tackling the "zombie problem" at hand.

both are historical genres with a dash of supernatural horror thriller, one is about ghosts and the other about zombies but they have the same promise

Zombies Zombies

Same genre, mutants, monsters, zombies..... If dark hole is ur cup of tea then kingdom will too. Although kingdom is waaay better than dark hole in my opinion

Both are about zombie apocalypse.
Be sure to watch all parts of Kingdom!!!
This GZ is set on modern times where as Kingdom is set in Joseon times.

Both are historical dramas (Kingdom has fantasy elements, though) with gorgeous cinematography and a unique, rich autumn-like color palette. The ML in both is the only child of the prior king who dies in episode 1 and the queen who was of lower position which threatened/threatens his position. In both he has a childless stepmother who is scheming to have him killed.