Author has written 8 stories for Harry Potter, How to Train Your Dragon, My Hero Academia/僕のヒーローアカデミア, RWBY, Young Justice, Supergirl, and Rise of the Guardians.
Games to play with your writer friends:
If anyone is familiar with the show RWBY, I recommend it. It's fun and has fascinating world-building, and some of the most interesting character design of any cartoon ever. Almost every character in that show is based on another character from literature or history, or sometimes desert, as is the case with Team CFVY. The RWBYfy game is simple: each player submits any character or figure to turn into a RWBY character. They're also given one character from another player that they must RWBYfy. Bonus non-existent points for drawing the subsequent RWBYfied characters, plus weapons if applicable.
RWBYfying characters includes a colour-based name, backstory, kingdom and unique elements of design.
If any of the characters become villains, huntsmen, huntresses, etc., then you must ALSO come up with a semblance fitting their character/story and a weapon for them to use (preferably named). If they have a team, a colour-based team name and possibly other characters should be RWBYfied.
For anyone else still confused, here's an example I've done.
Hiccup Horrendous Haddock III, RWBYfied
Name: Cassel "Hiccup" Haddock
Gear: Inferno and Tyr (Blowtorch/Flame-sword and Crossbow/Shield)
From a backwater village in greater Mantle, one that's adamant about not needing greedy huntsmen to keep them safe. His father, the chief, has a particularly strong hatred for them, as his mother left them after Hiccup was born to become a celebrated Huntress in Vacuo. Instead, they unlocked the auras of all their children from an early age and taught them the ways of a warrior. Hiccup's hatred wasn't very deep-set, but he did hold resentment for his mother, especially because the other children mock him for being the offspring of what they hate.
One day he's out gathering firewood when he stumbles into a bloody and broken woman, resting at the base of a tree. He tries to rush to her aide, but they're attacked by Grimm. Despite her injuries, the woman fights the beast off, worsening her own condition. Hiccup stammers that he doesn't have any money to pay her for the rescue, but she just smiles and says that she wanted to help people for the smile it could bring to their faces. Not for the lien in their pockets. Finally, she collapses due to her injuries and asks for his name. He tells her it's "Hiccup", what the other children would call him, and she laughs out loud before grasping his hand and giving her own: "Summer Rose", before succumbing to her wounds.
Hiccup was torn. His whole life he was told that huntsmen and huntresses were evil and that they exploited hapless villages for coin in exchange for protection against the growing tide of Grimm. Yet there he was, alive because of the actions of a huntress, an injured woman who helped him because it was right. Suddenly, his father's scathing words and jibes cut deeper than they ever did.
He couldn't take it anymore. In the dead of night, he stowed away onto his father's ship and flew to Vale. He got a job working for a jolly weaponsmith called Gypsum "Gobber" Grey, and his eye for detail and mind for innovation caught the attention of Beacon, who asked him to apply his schools in the aide of other students. In exchange, they would help him get certified as a Huntsman via an accelerated program.
Backstory doesn't need to be that long, or hey, it could be longer, but the point is to have fun with it. See if you can integrate the new character into the greater RWBY-verse.
It's not required but I prefer to keep all of my RWBYfied character canon-compliant, meaning that they tend to be background characters who don't actually interact with the characters in the show itself. Helps me fool myself into thinking that these characters do exist, tangentially, within the growing universe of Monty Oum (R.I.P.).
People to Check Out
KingRagnarok68 on this site (If links don't work, you'll have to search)
Curious_Teacup on AO3
Parsek on FFNet and AO3
Kleonauts: Rescue by Parsek
A Study in Scarlet by KingRagnarok68
Coeur Al'Aran (27)
Mr. Chaos (82)
Rorschach's Blot (41)
Temporal Knight (19)