Another scenario could be that an impostor, using some form of shape - shifting magic, disguises as a Gryffindor and does things that make it seem like Harry has betrayed the house first. As a result, the real Gryffindors, deceived by this false appearance, turn their backs on Harry.
Perhaps a plotline where Harry's abandonment by Gryffindor makes him more vulnerable to the influence of dark forces. He could be targeted by Death Eaters or other dark wizards who see his isolation as an opportunity. However, this could also lead to him finding new inner strength and ultimately proving that he doesn't need Gryffindor's approval to be a great wizard.
One possible storyline could be that some over - competitive Gryffindors bully Harry because they feel he gets too much attention. They might spread false rumors about him, like saying he cheats in Quidditch using magic. Another could be that they envy his connection to Dumbledore and try to isolate him within the Gryffindor common room.
A common scenario is when Dumbledore lies about Harry's family history. If he hid important details about Harry's parents or their relationship with certain dark forces, Harry would feel betrayed. Another could be Dumbledore giving Harry tasks that were actually much more dangerous than he let on, like sending him into a trap unknowingly.
One possible scenario could be a character being betrayed by a teammate. For example, Ruby might be betrayed by Weiss if Weiss is lured to the dark side by some powerful and evil force. This could lead to intense battles and emotional turmoil for Ruby.
Another idea is that there's a misunderstanding. Hermione might think Harry has done something truly unforgivable, like accidentally harming a loved one of hers in a spell gone wrong. Without proper communication, she jumps to conclusions and starts working against him, thinking she's in the right.
One possible plot development could be that Harry loses all faith in the wizarding world. He might go into hiding, constantly looking over his shoulder. Another could be that he decides to seek revenge on those who betrayed him, leading to a dark and dangerous path for him. Maybe he also finds an unexpected ally who helps him see that not everyone is against him and gives him the strength to rise above the betrayal.
One possible scenario could be Percy being betrayed by a primordial who he thought was an ally. Maybe the primordial promised him power to defeat a common enemy but then turned on him at a crucial moment, leaving Percy vulnerable and alone against a greater threat.
During a wizarding tournament where Harry is in danger. Gryffindor students would help him prepare. They might share secrets of magical challenges or give him tips on how to overcome difficult tasks. Their support and protection are crucial as Harry might not be able to succeed without their knowledge and assistance.
Well, in this type of fanfiction, it might be that Twilight Sparkle is betrayed by a mentor figure. This mentor could have been teaching her false information all along, causing her to make mistakes that put her and her friends in danger. Or it could be that she is betrayed in a love - related situation. For example, if she has feelings for a certain pony and that pony pretends to reciprocate only to use her for something else, like getting access to the library in Canterlot. There are so many directions this fanfiction could take.
Well, it could be that Draco betrays Hermione's academic trust. Since they are in a world where magic and knowledge are highly valued, he might steal her research or ideas for a spell or a magical discovery. This would be a huge betrayal as Hermione values her intellectual pursuits greatly. Also, he could betray her trust regarding a secret mission they are on together. He might abandon her in a dangerous situation, like in a dark forest full of dangerous magical creatures or in an old, enchanted castle filled with dark magic traps, just to save his own skin.