It really comes down to how you like to consume media. Reading the manga allows for your imagination to run wild, while the anime offers a more immersive sensory experience. You could even do both for a deeper appreciation!
You could start from the first volume. That's usually the best place to get into the story and understand the characters and world-building from the beginning.
There were a total of three movie versions of the Lightning King, which were " When the Lightning King's Blade Weeps,"" The Lightning King's Power of the God of War," and " The Eternal Legend of the Lightning King."
Which movie version he wanted to watch first depended on his personal preference. Generally speaking, it would be more appropriate to watch the Power of the God of War first because it was the first movie and had some basic content. However, if you liked Lightning King's work and wanted to better understand the plot and characters, you could directly watch When Lightning King's Blade Weeps.
As for the order, it could be viewed in the following way:
1 " The Power of the God of War: The Lightning King ": As the first movie, you can watch this work to understand the basic concepts and plot of the Lightning King.
2. When the Lightning King's Blade Weeps: This work is similar to the Lightning King's Power of the God of War. It is also the first movie in the Lightning King series. He could better understand Lightning King's story and character based on this work.
3. The Sequel to " The Power of the God of War "," The Eternal Legend of the God of War ": This work is the Sequel to " The Power of the God of War ". You can see the further expansion and development of the series of the God of War here.
The above are some suggestions for watching the movie version of Lightning King. I hope it will be helpful.