In certain comic arcs, Heimdall tragically meets his end. The circumstances and reasons for his death can vary depending on the specific comic series and plot.
Another theme is the exploration of power dynamics. Heimdall has his own powers and responsibilities, and when paired with an OC, it can create an interesting dynamic. Sometimes the OC might be in awe of Heimdall's power, or they might challenge him, leading to a more complex relationship.
In Heimdall x Reader fanfiction, a common theme is the struggle against fate. Heimdall may know the reader's fate, and the reader may try to change it, which creates conflict and drama. Another theme is the idea of seeing and being seen. Heimdall's all - seeing ability makes this a central aspect of the relationship. He sees the reader in a way no one else can, and the reader may strive to understand him in return. Additionally, the theme of sacrifice can be present. Heimdall might have to sacrifice something for the reader, or vice versa, as their relationship deepens.
In Thor vs Iron Man fanfictions, a really interesting plot twist is when the two are forced to work together against a common enemy. They start off as rivals but then realize that they need each other's skills. Another popular twist is when there is some sort of time - travel or alternate dimension involved. Maybe Iron Man travels to a time when Thor was a young and inexperienced warrior, or Thor finds himself in a dimension where technology is far more advanced than in Asgard and he has to adapt quickly to face Iron Man. These plot twists keep the fanfiction fresh and exciting for readers.
Well, it really depends on how the fanfiction is written. If the story focuses on Iron Man's technological advancements and his ability to quickly analyze and counter Thor's attacks, he might have a chance. However, Thor's raw power is not to be underestimated. He has centuries of combat experience and his powers are magic - based, which could potentially bypass Iron Man's technological defenses. So, more often than not, Thor has the upper hand.