the bosses fights are not as hard as the soulslike games. but some bosses are definitely challenging It's linear, not open world. this story is set after the journey of the west. some bosses have 2nd phase, if you defeat them fast enough in 1st phase(the time frame is unknown yet) there are 2 ways you can gain transformation/shapeshifting to defeated monsters(not all monsters), 1. obtain the weapon of the monster 2. capture defeated monsters with the gourd. method 1 you shapshift into the monster within a limited time frame, you change back to monkey after the timer expires or hp bar goes down to 0, basically gives you an extra HP bar. method 2 let you combine the monster's attack into your monkey attack combo seamlessly. the last but not the least, plz remember that this game is made by a 140ish employees studio, it might not be as polished as other games made by other bigger studios. Plz tune your expectation down, and enjoy!!!