Minecraft Ideas: Spears!
Weapons like the Trident and the Crossbow are some of my personal favourites since they break the norm of the classic wood -> stone -> iron -> diamond -> netherite upgrade tree. Since Mojang seems to be focussing on bamboo for the upcoming 1.20 update, I thought why not make some bamboo-themed weapons!
Spears are crafted using two bamboo and a flint, plus a banner if you want to customise it. They work like Tridents, both as a melee and ranged weapon and deal 2.5 hearts of damage, like a stone sword. To nerf them slightly from the powerful Trident, they have none of its exclusive enchantments like Riptide or Channelling but can have most other tool-based enchants.
Spears can be placed in the chestplate slot to form a banner hanging over the player's head, much like a Pillager's. If this item is too powerful for something so cheaply crafted, it could just be a temple loot exclusive.
I have no knowledge of modding nor do I have a PC so this remains purely a concept for now. If you have any critiques or suggestions, feel free to share!