It's a rather large change to the rules, but I've tinkered with a critical hit system that makes damage types more prominent. It will slow combat down a bit, and I'm not sure it's worth it. I haven't had a chance to try it since Corona.
First, in order to have crits happen more often, now a crit happens on a nat 20
or if you have advantage and both rolls hit.
Second, instead of dealing extra damage, crits have one of four effects. You choose, but different weapon types are better at certain types of effects.
- Bleed.
- Daze.
- Dent.
- Wound.
Bleed causes the creature to take damage equal to its hit dice at the start of its turn. It can make a Constitution saving throw at the end of its turn to end the bleeding, or a creature can spend an action and make a Medicine check to end the bleeding. The DC is 8 + your proficiency mod. If you inflict bleed with a
piercing weapon, increase the DC by 5.
Daze causes a creature to be unable to take reactions and its speed is reduced to 0. It lasts for one round. If you inflict daze with a
bludgeoning weapon, the creature also suffers disadvantage on attack rolls and ability checks.
Dent works for any weapon type equally. You damage something on the target, which might mean a weapon can’t be used, or might break off a piece of armor (or natural armor) reducing the target’s AC by 2. Or you could break some magic item they have.
Wound causes an injury. Roll 1d6 to determine location (and tweak based on monster type). If you’re wounding with a
slashing weapon, roll twice and pick which body part you hit.
- Eyes.
- Mouth.
- Chest.
- Primary Arm.
- Secondary Arm.
- Legs.
When a creature is wounded, it makes a Consitution saving throw (DC 8 + your proficiency mod). If it succeeds, the wound only affects until it takes a long rest. If it fails, the wound is permanent.
Eyes blind the creature for a round. Thereafter, the creature treats everything as having concealment.
Mouth means the creature cannot speak (such as to cast spells) or make bite attacks or breath weapons for a round. Thereafter it has disadvantage on attacks with the mouth (or saves against such attacks have advantage) and it cannot speak above a whisper.
A wounded chest cracks some ribs, inflicting a level of exhaustion.
A wounded arm drops what it’s holding, cannot be used to do anything for one round, and thereafter has disadvantage on anything its used for.
A leg wound knocks a creature prone and reduces its speed to 0 for a round, and thereafter halves its speed.
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The thing is, this works fine with enemies who might last a few rounds, but it’s kind of pointless for weaker foes. It’s all very tentative now.