Slightly Better Disarming (5e Variant Rule)
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Slightly Better Disarming
While 5e does have an optional rule for disarming (DMG pg. 271), it leaves a lot to be desired. Contests are something that 5e typically doesn't do and can make the BBEG simply lose the Sword of Macguffin from an unlucky roll, instead of players feeling like they did something impressive. Attacking as normal makes other potentially interesting variant rules (such as the disarming property) somewhat lackluster. Even something innocuous like allowing both Athletics and Acrobatics simply steals something that could make a pure Strength build worthwhile. Instead, consider the following:
When you want to forcefully take an item from a creature that is not a full set of clothes or armor, you can use the Attack action to make a special melee attack, a disarm. If you're able to make multiple attacks with the Attack action, this attack replaces one of them.
You may attempt to disarm a creature within your reach. If you are disarming the target of a weapon, make a Strength (Athletics) check with a DC equal to the target's passive attack roll with the weapon (10 + any bonuses the attack roll would have). If they are being disarmed of an item that is not a weapon, they instead use their AC. On a success, you may choose to put the disarmed item in one of your open hands, if any, or throw it a number of feet up to five times your Strength modifier.
If the item is magical and the target is attuned to it, you have disadvantage on the check. For every size category you are larger than the target, you gain a +3 bonus, and for every size category the target is larger than you, the DC gains a +3 bonus.
If you are using a weapon with the Finesse and Disarming properties, you may replace your Strength modifier with your Dexterity modifier for the disarm check in addition to the Disarming property's normal effects.