House Rules

Drinking Potions
Drinking a potion is only a bonus action instead of an action. Feeding a potion to another creature is one action.

Rolling HP
You may reroll any ones while rolling hp at a level up.

Underwater Spellcasting
Unless a creature can breathe underwater, casting a spell with Verbal components requires the creature to release some of the air in its lungs. A spell with a casting time of an action requires you to use up all the air, while a spell with a casting time of one bonus action uses half of it. When a creature runs out of air it starts drowning and falls unconscious after a number of turns equal to its constitution modifier.

Sharpshooter/Great Weapon Master
The relevant sections of the Great Weapon Master and Sharpshooter feats now read "-Prof./+x2Prof." instead of "-5/+10". So a character at lvl 1 with a proficiency of 2 can take a reduction of 1 * 2 to hit, but at an increase in damage of 2 * 2 (This is a nerf).

Lingering Injuries
The additional Lingering Injuries rule from the DMG will be used.

Inspiration
An alternative to inspiration involving random events based on fate will be used.

HP-based effects
Some spells or magical effects (like sleep or power word kill) has an affect on a creature based on their current hit points. Druid’s Wild Shape or a creature under the effect of a Polymorph spell have their hit points changed and thus becomes susceptible to these effects.

Casting multiple spells
If you use both your action and bonus action to cast spells during your turn, one of those spells has to be a cantrip.

Somatic components
In order to cast a spell with somatic components, you need a free hand. You can perform the somatic components of a spell with a hand that is holding a spellcasting focus.