The Prototype Rancour can be used by Bennett, Jean, Kaeya, Keqing, Qiqi, Xingqiu, and the Traveler. As it is a 4-star weapon, it has good stats, and it also has a passive ability called Smashed Stone: “On hit, Normal or Charged Attacks increase ATK and DEF by 4% for 6s. Max 4 stacks.