SteamWorld Dig 2 is an adventure platformer about a plucky explorer named Dorothy who delves into the rocky depths of SteamWorld in search of her friend Rusty, the previous entry’s protagonist. Dorothy’s journey takes her through more varied environments than Rusty saw on his adventure. She discovers ancient temples, primordial caves, and the ancient wreckage of the eldritch civilization Rusty tangled with, whose machinations are threatening the steam-powered robots of SteamWorld once again. Teaming up with Fen, a misanthropic energy spirit hunted by a SteamBot cult, Dorothy sets out on a grand digging adventure that will have profound consequences for SteamWorld and everyone who lives upon it.

At its heart, SteamWorld Dig 2 isn’t too different from its predecessor. I guide Dorothy down into the caves and mines beneath the boomtown El Machino, digging through layers of rock and soil in search of clues to Rusty’s whereabouts. Along the way I fill Dorothy’s bag with ore and precious gems. When I send Dorothy back to town, these valuables can be traded for upgrades to her lantern, pickaxe, inventory space, and other sundry tools she adds to her arsenal. These upgrades allow Dorothy to dig deeper, move faster, and survive longer. SteamWorld Dig 2 forges an irresistible loop of dig-reward-dig, enticing me with earning just one more upgrade or digging just a few dozen more meters before taking a break.

I must be careful how I direct Dorothy to dig through the dirt and rocks. She cannot jump and swing her pickaxe at the same time, so if I dig too far past a jewel or cave entrance I must climb back up to a horizontal platform and dig down once more in a parallel shaft. The resulting exploratory shafts through SteamWorld’s bedrock become a platforming labyrinth of my own creation, pockmarked by feral subterranean creatures and deadly traps left behind by those who came before.

Every few dozen meters, Dorothy discovers a cave entrance which contains a small platforming puzzle. It may contain a test of wits, tasking me with pushing minecarts or breaking specific dirt patches to reach an inaccessible tunnel or platform. Or it may be a test of endurance, pitting me against a glut of enemies or gauntlet of dripping acid and fire-spewing cannons. When I conquer the challenge, Dorothy earns valuable gems or a new tool to help on her journey.

What separates SteamWorld Dig 2 from its predecessor is scale. Instead of a single mine, Dorothy digs her way down into three separate shafts hidden beneath El Machino. The first of these, directly beneath the center of town, is similar to the shaft Rusty explored in his adventure. Other shafts are more creative, including an ancient temple filled with Indiana Jones-style traps and a cavern full of bioluminescent mushrooms that send Dorothy flying when she touches them. 

There’s more than just a visual difference. The shafts twist to the left and right instead of diving uniformly down, making it feel like I’m exploring a vast underground world of buried secrets instead of a plain mine shaft. With especially diligent exploration, I can discover shortcuts which join the three regions together. A comprehensive fast travel network makes these mostly pointless, but the cohesion created by interconnecting every region adds to the world’s sense of scale.

In addition to an expanded world compared to what Rusty explored, Dorothy gets an expanded arsenal to manipulate and traverse that world. A pressure bomb launcher lets her clear patches of earth too far away for her pickaxe to reach. Later, she earns a hookshot that pulls her to distant walls and ceilings. By the end of her journey, Dorothy barely seems to run through the warren she has dug beneath El Machino. She seems to soar.

These enhanced tools are put to great effect in the challenge caves. Finding my way from one end of these caves to another is usually only part of the challenge. The other is to use a tool in an unexpected or extra-challenging way to uncover hidden treasures and cogs. Treasures can be traded with an archaeologist in El Machino to unlock Mods that give Dorothy powerful new passive abilities.

Mods allow me to extensively customize the player character, limited only by the number of Cogs I have discovered which allow me to equip them. I tend to favor direct confrontation to solve most of my problems in a videogame, so I equip Dorothy with mods like Sharpened Edge to increase the damage her pickaxe deals and Healer to make up for the damage my recklessness often incurs. Players more interested in Dorothy’s steam-powered tools can focus on Mods like Storm Chaser and Moisture Vaporator that make her water tank more efficient. Players looking to uncover all the secrets buried beneath SteamWorld can take Mods like Sol Invictus, which highlights breakable walls. Thanks to these Mods, one player may have a completely different Dorothy from another’s by the end of their journeys.

The expanded and more imaginatively crafted world helps to make SteamWorld and its buried mysteries feel more like a real place. I come to care more about the setting and the characters within it, feelings the first Dig failed to elicit from me towards its mechanically functional but essentially soulless characters and world. It’s an important jumping-off point for the series, really setting the visual style and tone for the SteamWorld series that other entries build on. SteamWorld Heist, though released before Dig 2, is especially affected. The situations the SteamBots find themselves dealing with in that title are the ramifications of Dorothy’s actions in Dig 2.

It’s not essential to play Dig 2 to enjoy other SteamWorld entries like Heist and Quest, but its creation is essential for those titles to have a background and themes to build upon.

SteamWorld Dig 2 is a phenomenal example of how to craft a sequel. It takes the strong mechanics of its predecessors and expands on them with more ambition and ideas. Playing SteamWorld Dig is enjoyable; experiencing SteamWorld Dig 2 is a joy. It crafts a much larger world for me to play in, filling it with secrets to uncover and challenges to overcome. New characters with fun personalities and interesting designs are the final addition to a successful schematic, forging the series into one of videogames’ most dynamic indie franchises. It’s the most important videogame in the SteamWorld series and one of the best indie platformers of the 2010s.