Everyone has bad dice days. Everyone has that one time you get a Nat 1 at a critical moment.

But guys, my party is in trouble.

They’re consistently rolling terribly in combat across multiple sessions, classes, and dice types. And I mean terribly. Over time, you’d think their d20 rolls would average out to about unmodified 10, right? Plus or minus a bit. Hah. No. They’re averaging about 7. Other rolls (damage, healing, etc) also often suffer from this. It’s turning combat into a slog; anything with an AC of above 12-14 or so is proving awful to fight, and when attacks do hit they often do little damage.

We’re all experienced players, and it’s a digital platform - so I can both know they’re not missing modifications to the raw d20 roll, and know it’s not “bad dice”. Unfortunately, they’re also experienced enough to figure out ACs from misses/hits, so it’s not like I can even give them “free passes” on attacks as anti-frustration measures.

It’s at the point where I’m thinking the honest only way to “fix” this is to artificially nerf NPCs or vastly reduce the CR I’m used to them being able to handle. Is that really it, folks?

Altering the CR is my answer.

Not figuring out CR is why I was not a good DM, among other things. That you mention it at all tells me you probably have some semblance of a handle on it.

You really can’t fix it by artificially nerffing because assuming that the platform has random enough dice (which is most likely does for any real needs) the fact that they have thrown poorly before doesn’t mean that they will do so after your changes.

I don’t know how you are keeping track of the rolls but if you aren’t, I would first try that to truly see if it really is the case that the rolls are lower than average. Our memories of things going poorly aren’t objective and tend to enlarge amount of bad outcomes.

Why would a fix be required? It seems like you expect the bad rolls to continue.

Combat is always situational. Make their bad rolls have environmental consequences.

From a narrative standpoint, a bad roll doesn’t have to be a miss. They can hit a barrel of oil, or fish, and cause it to break open. Now everyone who isn’t a fishmonger within the spill area has disadvantage on all attack and save rolls.

Also, as dm, you never have to make your roles public.

Give them custom weapons or spells that are most effective when you roll low.

The luck system might be something to look into. It can help mitigate consecutive failures while maintaining balance.

You might consider adding a puzzle element to encounters that can lower the effective difficulty with clever maneuvers or strategies.

As an example, fighting in a room with a big chandelier overhead. A player can cut the chandelier at the opportune moment to pin a major adversary, allowing them to coup de grace or simply flaunt their victory to the villain’s face.

Or perhaps fighting in a room full of mirrors that allow a clever player to reflect a gaze attack. Or doing Battleship style combat, where you have to pick the square of a hidden enemy, but you guarantee a hit if you guess correctly.

In general, try introducing non-dice resolutions to the scene - guessing a magic word that disables a key piece of enemy tech, baiting enemies into an area or formation before springing a trap, completing a ritual that can summon a powerful ally by solving a rubric cube.

If all else fails, you can drop some nice loot them. Awand of fireballs or Staff of the Sun or similar high powered magic item, for instance. Doesn’t matter how you roll with these, you’re going to have some fun.

After I noticed this, to confirm it wasn’t just imagination I just started logging the roll results (d20s, at least) into an Excel sheet as we played. And yeah, they’re actually rolling that badly.

I have a rule as DM that I will never fudge rolls against the players, but I will fudge rolls in their favor if it fits the narrative. Three players consecutively miss an enemy? Oh no, next turn it got a critical fail and then failed a Dex save, slipping and landing prone. I guess the players get advantage on melee attacks! Don’t do this often, but I’m the right spot it’s fine.

Monsters can just be dumb, too. INT of 6 means those Blobby Blobs are gonna fight poorly, attacking the tank and splitting up attacks. Also, the players don’t know your monsters’ stats, so you can make an attack that would get it to 1 HP instead kill an enemy. I also don’t do this often, but sometimes they just get unlucky, and no reason to TPK.

Speaking of TPK, you can let them fail forward. Monsters rarely have reason to attack downed/unconscious PCs, so let them roll death saves, but it usually takes a while to die. Everyone’s unconscious? Stop combat, no more death saves. Instead, they wake up as prisoners and have to escape. I had a particularly fun one where my players would have died to a trio of night hags (if you’ve played Curse of Strahd, you know the ones). Instead, they woke up and were given a mission, but the bags also stole parts of their “souls,” taking Max HP from one player, speed from another, giving one a trait that they would lose all hope, stealing another’s eye (disadvantage on Perception), etc. Then they had to fulfill the mission, but later came back at a higher level and beat the hags, gaining their souls back. Everyone loved getting revenge!