No rolling of dice until the GM asks for a roll please. There is one exception - roll attack and damage dice at the same time.
Cocked dice follow the balance rule. If you can balance another die on top in 6 seconds then the roll stands, otherwise reroll that die.
Off-table dice are rerolled.
All dice rolling in public please (except for the Find Traps rolls - I roll them behind my screen mouahahaha!).
Two rules are in play to speed up combat.
When it is your turn in initiative, I will ask 'What are you doing?" If you can't answer straight away with what your character is doing then you lose your turn due to indecision and your character will stand still and take the Dodge action.
Use other player's turns to decide what your character is doing next.
This rule does not apply to the GM. I can't use your turns to decide what I'm doing next because on your turns I need to be concentrating on what you are doing.
With a few exceptions, the rulebooks are off limits during combat. You shouldn't need to look anything up in the PHB during combat - you should already have the information memorised or written on your character sheet.
If your character is a spellcaster then make a note of our spells. 150Ă—100 index cards are great for this (check out what I do with monster stats). Alternatively, buy the spell decks from Gale Force Nine or from the DM's Guild.
To make death a little more dramatic for the other people at the table, you will make your death saves in secret.
When a PC or NPC checks up on your character, only then announce to the rest of the table the results.
The really cool bit is, I don't actually care about what you really rolled. If you rolled well but you want to retire this character, say "He's dead." If you rolled badly, but you like the character and want to keep playing, say "She's alive." In other words, the death of your character is now your call.
Mostly. Rules like instant death through massive damage and death from cursed items still apply.
Your characters are professionals.
I'm assuming that they are paying attention to what is around them and staying alert (this is what passive perception is for!). I'm assuming they are gathering arrows and bolts after every fight and cleaning their gear during rests. You only need to tell me the exceptional stuff.
I'm assuming that they talk to other adventurers in taverns and swap tactical notes. They know a lot about things they have never encountered. For example, your characters know that trolls are vulnerable to acid and fire, even though they may have never seen a troll themselves.
So, if you ask me "Does my character know that trolls are vulnerable to acid and fire?" then I'm going to answer, "You tell me - it's your character."
Table-talk rules apply when in an Interaction scene. That means anything you say was actually said by your character. Very little retraction is allowed. This is called the Nick Pullar Gay Elf rule.
If you disagree with something I have ruled then say so. You have 60 seconds to argue your case. I'll then make a ruling and we'll continue. After the session has finished we will have a more in-depth look at the books and the forums. If I was wrong then we'll play it correctly in the future, but that evening's ruling still stands. We're only going to have two-to-three hours - we can't afford to spend 20 minutes discussing rules.
I'm trusting you with the metadata.
That means I'm going to tell you what the AC of the monster is, and you tell me whether you hit or miss. I'm going to tell you (or at least give you clues) that the monster is resistant to fire or vulnerable to acid. I'm going to tell you how difficult the fight is going to be.
This gives you a lot of power when using metagame abilities like superiority dice and bardic inspiration dice. The rules say that you get to decide whether or not to use these items after rolling the die but before the DM tells you the result. Well, you're going to know the result as soon as you roll the die. More power to you.
Note that inspiration is an exception to this. Advantage (and disadvantage) is taken before the two d20s are rolled.