Here is an easy to understand list of the alternative rules i am running in my games as Dungeon Master.

• What is a Critical Hit?
  • A critical hit in D&D 5th Edition is when a D20 is rolled for an attack roll and the result on the dice is a 20. This doubles the amount of damage dice you roll.

Brutal Critical:
When a critical hit is made, rather than rolling double the dice you instead maximize the possible damage done by the damage dice THEN roll damage dice as normal, adding the two together.
Both Friends and Foes have this rule in effect

Why this rule? This rule is added because players might get a critical then roll two '1's on their D10. this guarantees that a critical hit will always be more damage then a normal hit no matter what. Originally inspired by DM Kyle.

• What is a Skill Check?
  • A Skill check uses one of your many skills or your major stats. A roll of a D20 plus various bonus related to proficency and expertise equals the result of your skill check.

When rolling a D20 for a skill check friend or foe a critical failure (result of 1 on the D20) DOESN'T guarantee failure.
When rolling a D20 for a skill check friend or foe a critical success (result of 20 on the D20) DOESN'T guarantee success.

Why this rule? This Rule is implemented out of logic. some classes like to specialize in skill and some turn any result of the dice to be a minimum. Even on the result of a 1 a character may be so skilled that the result is still above 10 which means it may still succeed. Likewise some skills require a massive check due to their difficulty or absurdness. these should not be auto successes on a 20 even if it is hype.

• How do Potions work normally?
  • A potion is consumed using an action, the character then receives a flat amount of healing, then healing based on dice rolls dictated by the quality of the potion.

Better Potions:
ACTION: Potions may be used as an Action to receive the maximum possible healing.
BONUS ACTION: Potions can be used as a bonus Action to receive the standard D&D 5th Edition Healing amount.
THROWN: Potions can be thrown at a creature for healing requiring a successful attack roll.

• the creature takes the flat healing amount of the potion as damage as they are being struck by a glass bottle BEFORE Healing takes effect. The targeted creature must have at least 1HP to receive this healing

Why this rule? Potions kind of suck in Vanilla D&D way to expensive for unreliable effects. This aims to make them worth while and have more options giving them that Baulder's Gate 3 throwing option (But No AOE Healing), Feel free to increase their price as DM if using this rule.

• How is this different than the regular Massive damage rule found in the books?
  • Normally the rule requires a Constitution saving throw with a DC of 15 when the player takes more than half their maximum health from “A single source” I have altered it slightly so if a creatures takes more then half their health in a single turn they make the constitution saving throw.

System Shock:
When a creatures takes more than half their maximum health as damage in a single turn they must make a Constitution saving throw DC 15. on a failed save the player rolls a D10 to determine the result as their body goes into 'System Shock.“

• This is Less of a rule and more of a clarification of how I would handle a critical failure on an attack roll. Friend or Foe.

When a creature rolls a D20 that results in a 1 on an attack roll they will suffer a negative effect based on the situation such as dropping their weapon, tripping prone or taking damage.

Why this rule? As critical hits give hype boosts to Moral, Critical failure should have the opponent effect, It puts pressure on the party. It also applies to the ones they fight and its always funny when the troll gets a nat 1 ends up tripping and falling off the edge of a cliff.

• This List may remain Blank and entire campaign or be filled up as problems arise its up to the Dungeon master but should always be talked with the players about any restrictions. Spells should NEVER be flat out banned unless its unanimous in my opinion.

A list of specific spells that require their specific material components and cannot be ignored with a spell focus like normal, Materials with a gold cost still need to be paid.

• GoodBerry: Requires its listed component of Mistletoe.
  • Why?: The Abuse of this spell was expressed by players before the beginning of the campaign. as well as research online I decided to make the mistletoe component of this spell MANDATORY. so that situations of survival relating to scarcity of food couldn't be ignored.

Different to Inspiration points
Characters may revive Hero points at the end of a session based on Role play and actions performed.

• Players can use these Hero points to commit almost any crazy action they can think up so long as it can be justified in as logical or absurd way.
• Hero points vanish at the end of a session if not used.
• One hero point can be banked at the beginning of the session and can likewise be retrieve from bank if the player has no Hero points.
• A Limit of 2 Hero Points are handed out each end of session
• Secret effects only the Dungeon master knows.

Taken from Viva Dirt League's NPC D&D cause its a cool idea.

If players fail a skill check they can choose (If Dungeon Master Allows) to 'Take 20'
Depending on the skill check as dictated by the Dungeon Master they can allow the players 20 Un-interrupted Minuets in game time to automatically succeed on a skill check.
This may not be possible due to the nature of the task or environment it is up to the Dungeon master as each situations arises.

Why this rule? This allows players to retry a skill check with a penalty. things such as trying to unlock a door or move rubble.

If a spell requires a specific component with a gold value players can instead use the raw gold amount rather than the specific material if they don’t have the specific material.

Why this rule? This makes spell casters more streamline with casting spells. Though Spells that do not consume the item but rather require an item with gold value as the tool (Such as Identify requiring an item worth 100 Gold but does not consume it) I like to flavor that the gold is transformed into the tool. the player looses the gold but gains an item worth the amount for use with that spell.

Your characters gain a bonus feat as part of your background, this replaces the Background feature you would normally get. It cannot be an Abilities Score improvement and should relate to your background in someway.

Using Foundry VTT means its easy to track the weight of items on party members. Meaning if players hit thier maximum load teir speed is reduced to 0 as they have “Reached their Limit”

Taken from Viva Dirt League's NPC D&D cause its a cool idea.
When a skill, attack, save or otherwise results in a tie (example: Attack roll matching the Armor class) the result will always ac positively in the players favor.