There's so much going on in Critical Role's fourth Dungeons and Dragons series. With the 'overture' episodes concluded, the team has set up a lore-rich, politically complex narrative - one that's been impeccably acted out by its key players. There are many lessons to learn from the delivery of this big budget D&D game, but one tiny, crucial detail has stayed with me since campaign 4 began.
"You may roll Medicine with the Help action from another. The difficulty for this roll is 30."
There are many ways to sum up Brennan Lee Mulligan's DMing, but at this moment, 'deliberate' is the phrase that comes to mind. On the surface, this call seems run-of-the-mill. The party wants to learn something about a body that they are examining, and the information they seek is tough to find. The Dungeon Master sets the skill check and establishes the difficulty. Standard day at the D&D table.

The fascinating thing here, for me, is a decision that BLeeM has made behind the Dungeon Master screen. Any time a D20 test is called, the DM chooses whether to make the difficulty class public or private. It's a small, split-second decision that the Dungeon Master must make often, but it can have a surprising impact on play.
It's all about tone. In this case, Brennan Lee Mulligan has issued his players a bold challenge. DC30 is nearly impossible for a party of level-three adventurers. In making the DC public, he's communicated the sheer difficulty of the group's endeavor. They will most likely fail, but they still have to try.
The stakes are high, and this excites a party. They'll deliberate over the best person for the job. They might - as the Critical Role crew do - pump their chosen champion with buffs like Guidance and Bardic Inspiration. The difficulty class becomes a uniting force that brings the team together, and they'll share an epic few seconds of joy or despair, depending on how the dice roll.
There are examples of this on the opposite end of the spectrum, too. In the early episodes of the campaign, Brennan Lee Mulligan repeatedly shares the difficulty class of what turn out to be trivial rolls - DC10 or even DC5.
These checks are so easy to pass that failure would be comical. There is little tension in this moment, but the public difficulty class has still added stakes to the failure. Rather than disastrous consequences, it sets up a moment of levity if things don't go to plan, priming the players for their next character moment. It's a quiet moment of communication between a DM and players whose primary goal is to entertain their audience.
Most D&D players aren't performing for an audience when they play, but that doesn't lessen the power of the public roll. It's a subtle yet confident way to manage the tension levels at the table. And, while it may seem like an obvious tool at the DM's disposal, I know it's one I've personally neglected.
In my D&D games, I've always kept the difficulty classes for rolls strictly private. This can create tension for players but in a very different way. Here, the threat to a player is uncertain, and the anxiety it creates can be milked to add stakes to a scene.
This is something Brennan Lee Mulligan also does - not all his D20 tests have public DCs, after all. As an outsider, it appears that he relies on this when the line between success and failure is thin. Victory is possible, but bad luck is almost as likely.
The trouble is that you can have too much of a good thing. I can recognize the perks of my approach to dice rolls, but I'm self-aware enough to realize that I rely on it a little too much. And I know exactly why that is: a lack of confidence.
I'm currently DMing my first full DnD campaign. It's Curse of Strahd, because I saw all those Reddit posts saying it 'wasn't suitable for beginner DMs', and I decided that day that I couldn't read. While I don't think that I'm making a bad job of it, I'm definitely still learning the basics.
One such basic is setting the right difficulty class for D20 tests. There's a generally accepted scale that starts with DC5 for easy tests and DC20 for almost impossible ones, but this becomes less reliable as your players start to hoover up DnD level ups. Just look at the Critical Role crew, who, at just level three, have repeatedly bested the Big Scary DC20.
My players are now level nine, and I'm not always confident that I'm setting a difficulty class that's appropriate for the threats they face. On more than one occasion, The players have faced a task that's meant to be incredibly difficult, and they've breezed past the DC that I'd set in my head. Similarly, I've definitely set DCs in the past that have been far too high.
If your players don't know what the DC is, it's easy to tweak it ever-so-slightly before resolving the roll. This is - and let's call a spade a spade here - the controversial practice known as 'fudging'.

Lots of DMs do it, okay? Some might decide that, when the big boss has one hit point left, it'd be more cinematic to pretend that final scrap of HP wasn't there, giving the player an amazing killing blow they didn't technically earn. Others may, after watching the party almost one-shot an imposing enemy, silently add a 100 hit points or so. Some DMs are bold enough to fudge the rolls themselves, guaranteeing a success or a failure on their side of the screen that Lady Luck just wasn't handing over.
Everyone has a different tolerance for fudging in D&D. I personally belong to the school of "as long as it makes the game more fun for the players, it's okay". If it makes the story more interesting, I will occasionally indulge in some sweet, tasty fudge - though I'll never let the players know that I have done so (even when you destroy the sanctity of the dice, it's important not to break the illusion).
Fudging DCs is a safety net I created to try and serve the campaign's story better, but now I see I might actually be hindering it. Critical Role proves it's possible to show how the rabbit comes out of the hat and still create epic moments. All it takes is a bit of confidence.
How do you feel about fudging in D&D? Let us know in the Wargamer Discord. Or, if you'd like to do some roleplay of your own, here's all you need to know about DnD classes and DnD races.