Isekai manhwa refers to Korean comics where characters find themselves in otherworldly or parallel dimensions. It's a popular genre that offers exciting and imaginative storylines. Sometimes the characters gain special powers or have to overcome various challenges in these strange new worlds.
Betrayal is a very common theme. Usually, the protagonist is betrayed in their original world or in the isekai world they are transported to, which then triggers their desire for revenge.
The idea of revenge in 'isekai revenge novels' is appealing because it gives a sense of justice. When the main character is wronged in the other world, readers root for them to get back at those who did them wrong.
One popular 'isekai revenge novel' is 'The Rising of the Shield Hero'. In this novel, the main character is summoned to another world as one of the Four Cardinal Heroes but is betrayed and has to seek revenge. Another is 'Arifureta: From Commonplace to World's Strongest'. The protagonist is bullied and thrown into a dangerous labyrinth, and he embarks on a journey of revenge and self - improvement.
I don't know exactly who said it. It could have been a protagonist who came to this realization after going through a series of challenges and learning lessons about the futility of revenge.
'Arifureta: From Commonplace to World's Strongest' is also a'revenge isekai novel'. Hajime Nagumo was betrayed by his classmates in the isekai world. He then embarks on a path of self - improvement and revenge, becoming extremely powerful along the way.