You can try websites like Archive of Our Own (AO3). It has a large collection of fanfics, including those related to 'rwby berserker'. Another option is FanFiction.net. There are often many RWBY - related fanfics there as well, and you might be able to find some great 'rwby berserker' ones among them.
There are several places to look for 'rwby berserker fanfic'. First, AO3 as I mentioned before. It not only has a wide range of fanfics but also allows for easy filtering and sorting. You can set it to show the most popular or recently updated 'rwby berserker' fanfics. FanFiction.net is also a classic choice. However, be aware that the quality can vary more widely there. You can also look into some RWBY - related Discord servers. Some of them have channels dedicated to fanfic sharing and discussion, and you may find some hidden gems of 'rwby berserker fanfic' in there.
The best chapter pointer here is Chapter 33, "Variety Show of Villains". It opens with Following the announcement, five artists respectively reposted the Weibo—... and closes on Although Su Yinwan was considered half a goddess to him, the whole thing....
Look to Chapter 2 for the clearest answer. It begins with On the top floor of the Financial Building, a gathering of dark clouds..., keeps building through How dare Jiang Li hang up his phone?, and lands on Jiang, Lin Manru, turned pale and quickly explained, "It's not eloping, my....
Look to Chapter 36 for the clearest answer. It begins with But soon, people began to question the authenticity of Jiang Li's bare..., keeps building through After all, these days, faux bare-faced makeup can be indistinguishable..., and lands on After swallowing the food in his mouth, he hurriedly.
Chapter 33 is the strongest chapter-level answer because it starts from Following the announcement, five artists respectively reposted the Weibo—... and follows through on Although Su Yinwan was considered half a goddess to him, the whole thing....
Chapter 62 is the strongest chapter-level answer because it starts from Sitting on the edge of her bed, she pondered for a while before lifting... and follows through on Jiang Li reached in, pulled out a piece of paper, and slightly raised her....
Chapter 915, "Take out 1 million!", is the clearest early answer because it turns Take's situation into a concrete plot event. The chapter turns that into something concrete by moving from Hong Pei's expression was very unpleasant. to How can you just randomly insult someone?.
A practical answer is Chapter 60, because it turns the idea into a concrete scene. The chapter opens with What's with Jiang Yan, treating his own sister Jiang Li like this?" "He..., adds pressure through Jiang Yan, are you that lacking in confidence?, and ends on And in traditional characters?".
Chapter 930, "Everything Is Just Beginning [Grand Finale]", is the clearest early answer because it turns Jiang Yan's situation into a concrete plot event. Early on, Jiang Yan was in a daze until he was invited on stage..