Sooooo I kinda wanna throw in my opinion on what makes and breaks a Mary-sue. It isn't exactly the "be-all end-all" list of mary sue traits but like use it for reference.#1. Relationships with canon characters. Does not make a character Mary-Sue.
Now, if you have a character in relationship with a character from a video game e.g. Roxas from Kingdom Hearts it is completely fine. The character however, must exist in that Universe the OC is from, abide by the laws of said Universe and the canon character must not be "Out-of-character". If they are, then your character is a Mary-sue as they're basically rewriting the laws of a Universe to YOUR liking meaning that you're trying to edit an existing universe to your own accord. Also don't make your character like "i die from broken heart bc bae left me" like honestly and don't drone on and on how that character was meant for your character because chances are, other people are going to ship their characters with them and you have to accept that. Like ok, if you ship yourself with a character this shouldn't apply to you because you're not a mary-sue because A) You're not fictional, B) You're not perfect and C) It's just fun and games. Although your relationship can be serious I don't expect you to claim one famous character as your own. Like, shipping yourself with a character, at the end of the day is plausible but please don't get upset if people hate the ship because it is up to you whether the relationship is healthy and you're free to decide whom your partner is.#2. A character must be challenged. Characters are Mary-Sue if they're unchallenged by their canon.
Now, this is a broad term of "unchallenged". Basically it means your character must struggle against forces in their canon if they're referred to as "all-powerful". They must be mortal to an extent, meaning that they can be killed even if the procedure is complicated. A character with a pitch-perfect personality who loves their family and makes occasional mistakes IS a Mary-sue. If they're abducted, put into difficult to face with situations and fight a lot of powerful people but ALWAYS end up winning they're also a Mary-Sue. Don't do the "hit hit fall down, come back with power of friendship to defeat a deity leagues beyond them" because that's just cliché and noone will think your character is interesting.
For example, if your character must rally the help of people and needs the aid of an item to help them within interdimensional wars then they're challenged as they A) Need the aid of others B) Are not solely powerful enough to take on interdimensional opponents and C) Are not Mary-sue as they're not guaranteed to come out of this situation as there is always the chance they could die in these wars. #3. Powers and Traits of OC.
If someone claims your character is a Mary-Sue for being a God/Goddess please tell them to shut up. Your character can be a God/Goddess so long as they're not the God/Goddess of everything and can do anything they want. Broad terms such as Hope and Harmony are kind of unoriginal but otherwise fine. If they are the God of Death then you need to be careful how you write them (e.g. make them introverted and scared in case they kill things).
Also give them a learning curve with their powers. Don't make them knowledgeable about like a million things and have perfect and acute control of each aspect of their powers and able to detect other people's weaknesses and powers within like a glance. Like for Gods sake don't make your character use a fire spell straight away on someone who is weak to fire unless it has come to their attention from a previous incident or your character prefers this type of spell.
A rich, beautiful/handsome God/Goddess OC isn't an instant Mary-sue as if they're a God it is likely they can manipulate their visual appearance and can use their skills and abilities to earn a tremendous amount of wealth. Explain why they're rich and they're fine (e.g. God of Electricity generating mass amounts of power to earn a lot of wealth is fine). But don't make them "born into rich family that has millions of artefacts with tremendous power that they can use at very young age perfectly and grasp the concept of God-status and work to free the world of evil" because that is
without a doubt Mary-sue. A young child should be starry-eyed about saving the world but should come to hate the responsibility and fear the power they wield. They shouldn't interact with their surroundings because they're scared in case the ones they love are drawn into the fight.#4. Nitpicks
Don't make your OC like 1,000,009 years old or anything like that and make them "looks 9 years old". If your OC's species ages slower than other species, make it a consistent rate. E.g. 700- looks 7 not 1007- looks 7. Don't add their physical age onto a big number, make it a consistent rate. This is only acceptable if they're considered say 1007 because they were born 1000 years ago but had started forming an age at 1000 (e.g. Orb of light 0-1000, baby 1001-....).
Give them a unique personality not "loves family and will protect them at cost of their life" especially when they can't die because it doesn't make sense.
If your character makes mistakes it doesn't excuse them from being a Mary-sue. You need to give them flaws as your character can be ditzy and clumsy but have an overwhelming power that can rid their mistakes in an instant, making their flaw redundant. (E.g. Your character is a perfectionist and tries to show off, leading to their downfall. Is fine. "Your character loses 5 crystal gems that are Sacred and essential to the Universe but they effortlessly track down each one and said Gems have been enchanted by a spell by said character to conveniently not be used for evil".
Also don't make up gems, metals, etc. Why not pick an actual one e.g. Diamond, Topaz, Alexandrite, Malachite, etc. and make your character enchant them or give them a special property you're wanting.
Don't make your character flawlessly good looking along with proficient in every single weapon they pick up with amazing powers whilst being able to protect all of their friends and able to defeat any enemy with a power exclusive to a certain species. Instead you should-
- Make them very nitpicky about their appearance and use makeup and expensive products to maintain their skin/beauty
- Make them adept at one weapon at most unless the weapons are very similar (e.g. guns+ other guns, sword +other swords)
- Give them few select powers or give them a variety of weak powers (e.g. "levitation to the point they can only do it for a short time and not very high" would be an example of a weak power)
- Make it a struggle for them to protect all their friends and don't make them kill any enemies within an instant, make the fight elongated and realistic rather than "u have my frend *KILLS ENEMY*"
- If you really want the power either change them to that species or make your character have a mimic of the power. I done this with my OC Tekina. I saw Yaksha from Hero 108 and thought the idea of an article of clothing with malleable abilities was a good idea, so I converted Yaksha (a hat) to a scarf.