* Trolls: Bilbo first encounters three trolls named Tom, Bert, and William. They capture Bilbo and the dwarves, but they are eventually turned to stone by the rising sun.
* Goblins: After escaping the trolls, Bilbo and the dwarves encounter a group of goblins. They are chased through tunnels and caves until Bilbo manages to escape into a deep hole.
* Giant Spiders: While hiding in the hole, Bilbo encounters a group of giant spiders. He escapes their clutches by using his wits and a small knife.
* Gollum: After escaping the spiders, Bilbo finds himself in a dark and gloomy cave. He encounters Gollum, a creature who lives in the darkness and collects things as a hobby. This encounter leads to Bilbo discovering his own courage and resourcefulness.
While Bilbo also encounters other creatures like bats and worms, these are the primary ones with significant interactions and influence on the story's progression.