Hua Cheng is such a gorgeous character because you must realize that he becomes a calamity class ghost king, one of the notorious four supremes, out of /love/, not out of hate
He builds himself up and obtains so much wealth and power and strength and ferocity and knowledge for love.
The four supremes have all done objectively horrible things, terrifying things, amoral things. Even Hua Cheng has done things that most people would consider to be “evil”.
He is the embodiment of that line from Guillermo del Toro’s movie Crimson Peak: “the horror was for love”.
But also! He destroys and sows chaos and strikes fear into the heart of heaven and rules with an iron fist FOR LOVE, and yet he also builds and creates FOR LOVE
The same person who ruined 33 heaven officials, rained a shower of blood on Qi Rong’s nest, is also someone who builds temples and sculpts statues, farms, built a manor and carved a door and collected treasures all for his love
Hua Cheng is such a big contradiction against the prevailing notion in literature that only heroes/good people can find genuine love and be genuinely devoted and get a happy ending