Here is a videogame idea for Avatar the last airbender TV show , I have not played any videogame based on this cartoon before so I'm not sure if this has been done before.
So basically it should be a single player open world game with some rpg elements such as leveling up and learning new techniques, you can follow the main story of the original show and at the same time you can do sidequests based on the TV show as well. The gameplay will be a beat'em game, nothing fancy or complicated just straight up beat'em up.
You will have your standard health bar and chakra bar for the elemental techniques, the action buttons will have light attack, Heavy attack, block and varied techniques depending on the character such as cure, traps, etc.
You can switch and replace new techniques learned (kinda like pokemon) as the more you level up you will learn more powerful techniques, this cannot be done during combat so will need to have the techniques assigned to your controller in advance before combat.
Aang will be the only character to learn techniques from all 4 elements, although some techniques will be character specific like water cure for Katara and metal bending for Toph. Aang will also be the only character to go into Super Avatar mode.
You will be able to play as other characters as well, specifically the members of Team Avatar with Aang being your main character and the strongest of course. During the gameplay you will be able to select teammates for missions and switch between them during combat, as well you can level your teammates to a certain degree. Main story missions will require you to play as certain characters but you can freely select or switch between your teammates on other side missions or side events, note that Aang must always be included on your selected team.
Since its an open world game exploration will be rewarded, you will able to find costumes that will grant you a special skill or advantage for your characters, as well as scrolls thats will contain techniques to learn and obviously health and chakra upgrades.
As you progress through the main story you will unlock new areas on the map to explore, you can play side quests and some will be specifically for certain characters. Some hidden places will have doors to the spirit world where there will be more challenging quests or activities and special rewards
Appa the Flying Bison will be your main transport.
You will have your camp base where you can rest, switch between techniques , costumes, do some training and other activities.
Boss battles will be different, from the most popular antagonists of the show , Huge beasts and of course the Fire Lord himself.
As a post game extra, you will be able to use Aang to go into the spirit world and challenge the 4 previous avatars, they will be 4 different boss battles, they will be among the most difficult bosses of the game since they will have top tier techniques and the ability to go into Super Avatar Mode.