These are all really fun, creative ideas! I love the idea of wrangling spirits, or having knotted strings and bags of beads...
I'm not planning on running a Prehistoric Campaign any time soon, but I kind of like this idea for weapon breakage. Keep in mind I'm literally making this up off the top of my head! This would also, in my mind, be supported by Encumbrance and scarcity rules, making it pricey to break your weapons.
Melee Weapon Breakage
When you roll a melee weapon attack that misses, you may choose to break the weapon, adding 1d4 to the attack roll. Depending on the weapon's damage type, the following effect occurs:
- Piercing: Shards of the weapon stick into your target. At the start of each of your turns, they automatically take piercing damage based on the size of the weapon (light: 2, one-handed or versatile: 3, heavy: 4). As an action, they or another creature may remove the shards, ending the effect.
- Slashing: Your final blow opens a gash in the target's armor. Their armor class is reduced by 1.
- Bludgeoning: The stump of your weapon may be used as a Shield, granting you +1 to Armor Class, even if you are already wielding a shield. If you use the stump to attack, it acts as an improvised weapon and is destroyed.
Ranged Weapon Breakage
When you hit with a ranged weapon attack, you may choose to break the weapon, gaining one of the following benefits:
- Long Range: The attack ignores disadvantage for attacking at a far range.
- Deadly Aim: The weapon deals maximum damage on its weapon dice.
- Distraction: You may attempt to hide as a bonus action.
Spell Sundering
After you cast a spell, you may choose to sunder your connection to the magic, drawing more power from breaking your pact to the spirits or materials you rely on for arcane might. You may not cast that spell again until your next Long Rest, even if you have spell slots available. Choose one of the following effects:
- Spell Barrage: Cast a Cantrip as part of this action.
- Unbreakable Magic: If the spell requires Concentration, you automatically succeed on Constitution Saving Throws to maintain concentration, as long as you are conscious.
- Fickle Fates: You force one target to reroll their Saving Throw against your spell, taking the new roll instead.
However, you must also roll for a cost:
- Magic Blast: The spell component pouch or arcane focus you use to cast the spell is destroyed. If the material used for the spell is usually consumed, or the spell does not require materials, you instead take an amount of Force damage equal to your Spell Attack Bonus.
- Blood Contamination: You are poisoned for the next hour. This effect cannot be cured by magic or medicine.
- Eyebite: You are blinded for the next ten minutes. This effect cannot be cured by magic or medicine.
- Weakened Spirit: You gain one level of Exhaustion.
- Greater Sundering: You may not cast spells for one minute.
- No Effect: The fates smile upon you!