There's 'Konosuba: God's Blessing on this Wonderful World!'. While it's more of a comical take, the goddess Aqua can be seen as an 'evil god' in some aspects, especially from the main character Kazuma's perspective. She's self - centered and causes a lot of trouble for him. It's a really fun light novel with a unique take on the isekai genre and characters that seem to have 'evil god' - like traits at times.
One popular 'evil god' light novel could be 'Overlord'. In this novel, the main character has a rather 'evil' presence in the new world he finds himself in. He rules with an iron fist in a sense, and there are many elements related to power, strategy, and a different kind of morality. Another one might be 'Re:Zero − Starting Life in Another World'. The Witch of Envy can be considered an 'evil god' - like figure in the story, and the complex plot that revolves around her influence makes it an interesting read.
I would also suggest 'Grimgar of Fantasy and Ash'. Although not as obvious as the others, there are elements that can be related to an 'evil god' concept. The world is harsh and there are hidden forces at work that could be interpreted as such. The characters' struggle against the unknown and the difficult world they live in can be seen as a fight against an almost 'evil god' - like entity that controls their fates.
Chapter 10, "Long-tongue Snow Mane", is the clearest early answer because it turns Snow Mane's situation into a concrete plot event. The setup is At first glance, this Ice Tree appears no different from the other..., but the pressure keeps building through The trunk is covered in white snow, and the canopy is also adorned in....
Chapter 146, "Rage, Murder, Ferocity", is the clearest early answer because it pushes Redwood Ridge into a new phase or setting. The chapter gives readers a real answer by opening on Xia Chuan's laughter affected Luo Yuan and Yue Feng as well, and they... and ending on As these people gathered around, they retrieved the Iron Arrows.... In story terms, the danger stops being abstract and the conflict around Redwood Ridge becomes immediate, forcing the surrounding cast to react under pressure.
Chapter 434, "An Enemy Commander In Delwig", is the clearest early answer because it turns Damien's situation into a concrete plot event. It opens with Apnoch opened his mouth to respond—but Damien's hand shot out,... and closes on Before Damien could trace it further, the vision fractured..
Chapter 432, "I Can Feel It Through My Summon", is the clearest early answer because it turns Damien's situation into a concrete plot event. A useful checkpoint is the way the scene starts with The morning mist hung low over Delwig's outer walls, pale and... and follows through with I can feel it through my summon.. By the close, Lyone followed after, settling himself just behind her., and the chapter closes with Damien's smirk returned, faint and dangerous. "I don't need to be sure.
Chapter 118, "Poison Sac, Making a Bow [2-in-1]", is the clearest early answer because it turns Xia Hong's situation into a concrete plot event. The chapter turns that into something concrete by moving from Leader, Yuan Cheng has woken up!" As soon as Xia Hong stepped out of... to As the temperature of the leather bag rose, the Teng Jiao Poison sack....
Chapter 6, ", Moving", is the clearest early answer because it turns Xia Hong's situation into a concrete plot event. The setup is The entrance was quickly sealed by over a hundred people working..., but the pressure keeps building through Although there was firelight in the cave, once the entrance was....
Chapter 457, "Mass Burial", is the clearest early answer because it turns Damien's situation into a concrete plot event. Early on, The morning after the battle was a quiet one.. By the end, By the end of the second, the silence had become ritual.. Inside the broader faction conflict storyline, the chapter closes with He didn't promise. He just turned toward the city center and began walking., which gives power growth a stronger narrative position and pushes the power growth onward.
Chapter 116, "Great Righteousness, Hunting Flood Dragons, Saliva [Five-in-One Mega Chapter]", is the clearest early answer because it turns Teng Jiao's situation into a concrete plot event. Early on, Their preparation was exceedingly thorough; they followed Xia Hong's.... By the end, Amidst dealing with so many attacks, Teng Jiao's sweeping strike....
Chapter 120, "Unusual Rat Movements, Frantic Bow Making [Large Chapter]", is the clearest early answer because it turns Xia Hong's situation into a concrete plot event. A useful checkpoint is the way the scene starts with In the Ice Abyss World, the average lifespan of ordinary people is... and follows through with We still have to hunt Jiao tonight; we're out of spinal cords!.
Chapter 407, "First Night In Delwig", is the clearest early answer because it turns Damien's situation into a concrete plot event. It opens with The guesthouse Apnoch left them in was far from ordinary. and closes on So why did these new deviants suddenly show up?. The key payoff is that the chapter closes with Damien arched a brow but sheathed his blade. "Lead the way., which gives First Night In Delwig a stronger narrative position and pushes the family politics onward.