Core Keeper expands with Riders of the Underground, a free update bringing mounts, a new sub-biome, and improvements that make exploring even better
In Core Keeper, heading out to find some ore can end in a home renovation, an unplanned expedition, and a fight you really should have packed more food for. Its ability to turn small ambitions into an increasingly ambitious to-do list remains its biggest draw. Riders of the Underground understands that appeal, offering fresh excuses to get lost underground and, crucially, tools that make the journey less of a chore.
Pugstorm’s game entered Early Access in 2022 before reaching its 1.0 release in August 2024. Released on September 21, 2026, the free 1.3 update builds on an adventure that had already found its own identity somewhere between the construction of Minecraft and the progression of Terraria. The interesting question is how much it improves what happens between one discovery and the next.
The Joy of Turning a Cave Into a Home
Comparing it to those two giants helps set the scene, though it leaves out some of its charm. Core Keeper combines conquering the underground with the pleasure of settling into it. Planting a garden, organizing a base, and automating resource gathering all belong to the same adventure as battling enormous creatures. Home is where you prepare for your next questionable decision.
Skill trees and equipment combinations add another layer of progression. Finding better materials matters, but so does deciding how to develop your character. The interplay between building, exploration, and combat lets you switch goals without feeling as though you’ve abandoned your adventure. With co-op supporting up to eight players, there’s room for the person who wants to conquer the world and the one who thinks fixing the dining room is more urgent.
A Mount Means More When You Have Somewhere to Go
The headline addition in Riders of the Underground lets you turn livestock into mounts by equipping them with a saddle. You can also name them and adjust their behavior when you’re not riding them. It’s a particularly fitting addition: it connects animal care with exploration, giving creatures that already belonged around your base a new role beyond it.
The Hookshot, meanwhile, attaches to solid surfaces and pulls you across water and gaps. This is one of the update’s smartest ideas. In a game built around digging, every obstacle presents a small decision; another traversal tool gives you another possible answer. Building a route still has value, but crossing a single gap doesn’t always need to become a public works project.
There’s also Moss, a new sub-biome within the Forgotten Ruins and home to the Orex, a prehistoric-looking creature considerably more docile than its silhouette suggests. That distinction in scale matters: it enriches an existing region rather than adding a full standalone biome. Anyone expecting a huge expansion should temper their expectations; the appeal lies in giving you something else worth investigating along the way.
The Most Important Change Doesn’t Wear a Saddle
Summoned minions no longer disappear after a set amount of time, and you can now summon as many as your character allows in a single action. Removing the need to repeatedly renew your companions eliminates a maintenance task that competed with combat for your attention. It’s less flashy than a rideable dinosaur, but it’s a sensible improvement to that playstyle.
Magic gets adjustments too: mana continues regenerating at reduced effectiveness while you attack. The patch also introduces equipment comparisons and streamlines parts of progression and crafting. Taken together, these changes suggest an encouraging approach: Pugstorm is reconsidering how much busywork its adventure demands while adding more things to do.
You Still Have to Enjoy the Mining
None of this changes the underlying proposition. Gathering, crafting, preparing for an expedition, and doing it all again remain central to Core Keeper. If you enjoy establishing your own routine, that repetition has its rewards. If you need constant novelty or clear direction, it can become a slog. No mount can fix a fundamental mismatch with the genre.
It’s also worth distinguishing a good update from a reinvention. Riders of the Underground offers reasons to return, particularly for players who enjoy experimenting with character builds and ways to get around. Its appeal is more limited for someone who has exhausted the game and wants an entirely different adventure.
Verdict: 8/10
Core Keeper remains an easy survival-crafting recommendation, with a remarkable knack for turning small goals into grand projects. Riders of the Underground strengthens that appeal with mounts, new traversal options, and adjustments that ease repetitive tasks. Its scope is the main limitation: it improves an excellent formula, but it’s unlikely to win over anyone who never enjoyed that formula to begin with.
Getting these additions for free more than two years after the 1.0 release adds value, though the design decisions deserve most of the credit. There are new things to discover underground and better tools for reaching them. If you still have an unfinished tunnel waiting somewhere, here’s a good excuse to return. Logging off before you start expanding the house, however, remains your responsibility.