It's a bit tricky to pinpoint exactly where the 86 anime ends in the light novel. Sometimes it depends on the adaptation decisions made by the production team. You could try looking for detailed comparisons online or in fan communities.
I'm not sure exactly, but you might be able to find that information on dedicated anime forums or by asking fans who have read the light novel.
Chapter 253, "Short on Meat, Short on Manpower, Someone Delivers (Part 2)", is the clearest early answer because it turns Great Xia's situation into a concrete plot event. A useful checkpoint is the way the scene starts with Beehive 129, last night Hanqiong's 1259, with the newly added... and follows through with The camp's beast meat gap cannot be too large!. By the close, Our stockpile of beast meat is considerable;
Chapter 156, "Mirror Immortal, 10 Days to Gather Beast Blood", is the clearest early answer because it turns Yuwen Hu's situation into a concrete plot event. The chapter gives readers a real answer by opening on Do you think the leader's decision was meant to exclude us?" "What... and ending on As the Teng Jiao fell, Xia Hong, without a moment's hesitation,....
Chapter 147, "Massacre, Encounter with Cold Resistance Level [Huge Killing Chapter, Seeking Monthly Pass]", is the clearest early answer because Xia Hong finally turns buildup into a real advancement. Early on, Moreover, after He Meng felt his strength, he showed a look of shock.... By the end, The broadsword was aimed upward first, then swung up..
Chapter 233, "Army Sets Out, Yang Lu's Transformation, Mid-stage Cold Resistance", is the clearest early answer because it turns Xia Chuan's situation into a concrete plot event. It opens with Great Xia Valley, Main Hall on the Top Floor As usual, the main seat... and closes on Over 700 square kilometers, more than 29,000 people, and four Cold....
Chapter 188, "Venting, Drawing Lines, Preparations", is the clearest early answer because it turns Xia Hong's situation into a concrete plot event. The setup is Chen Yingba hadn't finished speaking when he saw Xia Hong flick his..., but the pressure keeps building through But before his body could move, a sharp whistling sound had already....
Chapter 160, "Night Has Fallen, The Time Has Come", is the clearest early answer because it turns Xia Chuan's situation into a concrete plot event. A useful checkpoint is the way the scene starts with The pressure on the more than a hundred people holding the front door... and follows through with It is said that even against the Intermediate Cold Beasts like Teng....
Chapter 183, "Population Explosion, Valley Planning", is the clearest early answer because it turns Xia Chuan's situation into a concrete plot event. It opens with Qiu Peng spoke as he handed over the register. and closes on The regulation is rational, but the current personnel quality doesn't....
Chapter 235, "The Might of the Longyou Army, Yang Lu's Desperate Plight", is the clearest early answer because it turns Yangyuan Peak's situation into a concrete plot event. A useful checkpoint is the way the scene starts with On the night of April 14, Xia Hong indeed personally witnessed the... and follows through with Yuwen Dao sighed inwardly while seeing a large mass of Longyou....
Chapter 166, "The Defenseless Mirror Immortal", is the clearest early answer because it turns Meng Yi's situation into a concrete plot event. A useful checkpoint is the way the scene starts with Xia Hong, my leader, among our three thousand people, none have paid... and follows through with An Iron Arrow was struck down by Xia Hong, and immediately several....
Chapter 185, "New Home, Land, Arrow Bamboo Forest", is the clearest early answer because the buildup finally cashes out in a real clash. The chapter gives readers a real answer by opening on This number is really too tempting! and ending on While doing so, let's see if there's any other human camp on the....