I'm not sure which specific story Gandalf is telling as there are many in the Tolkien's works. Maybe it's about the history of Middle - earth, like the battles against the dark forces or the tales of the rings.
Well, Gandalf is from the Ainur. He was among those Maiar who were sent to Middle - earth. His purpose was mainly to help the good against the forces of evil like Sauron. He was created long before the events in Middle - earth started to unfold. Gandalf's origin story is deeply intertwined with the greater cosmology of Tolkien's world. He had powers that were both magical and related to his wisdom and knowledge, which he used to influence the course of events in Middle - earth.
Gandalf originated from a higher spiritual plane. He was dispatched to Middle-earth with a purpose. His background involves being part of a divine order and having a responsibility to bring hope and resistance against evil.
Well, one similarity could be in the style of their design. Beemo is a cute and unique character in Adventure Time, while the Balrog in other stories often has a very distinct and menacing look. In Cave Story, the characters also have their own unique design styles. They might all share the aspect of being part of a world that has its own set of rules and lore. Another similarity could be in their role in the overall narrative. Beemo is important for Finn and Jake's adventures, the Balrog often serves as a major obstacle or threat in its own story, and in Cave Story, characters play crucial roles in the journey through the cave world.
Gandalf is a Maia. He was sent to Middle - earth by the Valar. He was one of the Istari, a group of wizards. His purpose was to guide and oppose the rising power of Sauron.
Beemo's abilities are centered around being a useful companion in the Adventure Time world. It can interface with other devices, play music, and keep Finn and Jake entertained. The Balrog is a force to be reckoned with, having abilities that are designed to be a major threat. It can cause destruction and overpower opponents. In Cave Story, characters' abilities are a mix of offensive and defensive. Some characters can create shields, while others can launch projectiles. These abilities are different from Beemo's non - combative tech skills and the Balrog's more dominating physical abilities. The diversity in Cave Story abilities also reflects the more complex gameplay compared to the more straightforward roles of Beemo and the Balrog in their respective stories.
The fact that Gandalf is from the Ainur is a very important part of his origin story. Also, his transformation into the form of an old man is significant. It allowed him to interact more easily with the races of Middle - earth, like humans, dwarves, and elves. And of course, his being sent to oppose Sauron is a central aspect of his origin. It shaped his entire journey in Middle - earth.