Struggling with Low-Level Encounters – Am I Doing Something Wrong?

[shamss01]

Hey all!

I’m pretty new to D&D 5e and currently running a homebrew campaign for a group of friends. We’ve had a blast so far, but I’m hitting a bit of a snag when it comes to balancing encounters for low-level characters (they’re all level 2 right now). I keep running into this issue where the fights either feel way too easy, or I nearly wipe the party, and it’s got me feeling a bit lost.

Here’s an example: Last session, I threw 4 goblins at them, and they mowed them down without breaking a sweat. So, in the next encounter, I bumped it up to 6 goblins with a bugbear leading them. The fight immediately turned into a bloodbath, and my players were one hit away from a total TPK. I had to seriously tone down the bugbear’s damage mid-fight to avoid disaster.

I’ve been using the encounter-building guidelines in the Dungeon Master’s Guide and some online calculators, but it still feels really unpredictable at low levels. Sometimes a creature that looks weak on paper ends up nearly killing them with a lucky hit, and other times they steamroll everything.
A few questions for the seasoned DMs out there:

Is this normal at low levels? I know characters are squishier early on, but it feels like the difference between success and failure is razor-thin.

How do you handle swingy encounters like this? Do you fudge rolls or modify monsters on the fly? Or just let the dice fall as they may? I don’t want to constantly adjust things mid-fight, but I also don’t want to kill my players in what should be a minor skirmish.

Any tips for balancing encounters better? Should I be leaning more on terrain, traps, or environmental hazards to make things interesting without it just being a slugfest?

Player strategy: I feel like my players aren’t using their abilities to the fullest yet (we’ve got a Fighter, a Druid, and a Rogue). Is that common at low levels? Should I be nudging them toward smarter tactics or just let them figure it out?

Would love to hear your thoughts on what’s worked for you! Thanks in advance! :)

[Sibelius Eos Owm]

This may come a bit late for you to be checking still, but maybe this will find its way to you eventually. I don't know a whole lot about 5e encounter balance, but one thing I've heard a lot about is that because of the way its math works, adding more enemies can dramatically alter the threat of the fight. In particular, the moment that there are more foes than there are PCs is a tipping point where the enemies have more total actions than the heroes, so the heroes have to play catch-up.

An unfortunate reality of 5e is that CR is only a loose guideline at times, and random chance can alter the feel of a fight a lot (if more than half the goblins hit and less than half the PCs do in any given round, it can turn the fight into a struggle.

In the case of the fight with the goblins and bugbear, I feel like it would have been better to either increase the numbers or add the hobgoblin, rather than both. I can see why it might have felt like both were necessary for a challenging fight when 4 goblins were a cakewalk, but at low levels fights can get really swingy.

Good news is, the swinginess eases up a little bit as you go up in levels. The only other advice I have is to find and watch Matt Colville's Running the Game series on YouTube. I think his first video uses an example specifically about how the number of goblins in a fight can turn an easy fight into a struggle just because there's more creatures on one side than the other.

Good luck and have fun!