Core Keeper Playthrough: Defeating Bosses and Automating a Base in the Underground World

Right after being sent to the underground world, the player first gathers wood, crafts a wooden pickaxe, and mines the surrounding copper ore. While the copper ore is smelting, the player starts farming with seeds they picked up and gradually sets up a living base.

Near the base, the player finds a slime area and advances by defeating enemies little by little with hit-and-run tactics, eventually discovering the boss of the slimes. At this point, the player decides to retreat for now and take it on after preparing properly.

As preparation, the player first sorts out food and expands the farmland with seeds gathered along the way. According to the narrator, boss fights in this game are basically fought in a "stuff a ton of food in your mouth and fight" style. The player switches weapons to a bow for ranged attacks and upgrades armor to copper gear.

In the battle, a raincoat that reduces the effect of the sticky floor and a bow that can be fired while running around worked well. However, it was a hard-fought battle in which both sides were whittled down to the very edge, and the narrator looks back, saying, "One more stomp and I'd have been dead."

The defeated slime dropped a treasure chest and an "old man" appeared. Placing the stone dropped by the boss into a statue at the base unlocks an item that reveals the locations of other bosses. This system shapes the flow of exploration from here on.

The next boss appears to be circling around the area, so the player decides to expand the exploration range for a while. While digging onward, the player obtains a musket, which according to the narrator has eight times the attack power of the bow, boosting combat strength in one go. The pickaxe is also upgraded from copper to tin, making it possible to dig into a new area with harder walls and unlocking iron ore.

Lying in wait on the boss's patrol route, the player fires bullets into it as it passes by and keeps firing after it goes past, whereupon the boss changes into a rage mode and starts circling around the area. The player keeps pouring musket fire into it and defeats it easily. The rewards include an item that increases inventory slots and a stone for the base; this stone unlocks recipes for useful items, and the player becomes able to teleport back to base using a consumable item.

Scanning for the next boss's location reveals that it is in an area even further ahead. Going there, the player finds a creepy creature and starts the battle after clearing out the surrounding enemies. This boss is said to be troublesome because it produces a liquid that deals gradual damage when stepped on and eggs that keep spawning enemies unless destroyed. Using a newly crafted iron spear, the player deals with them bit by bit and defeats the boss despite being chased around by small fry.

The rewards are material for a legendary weapon, a stone for the base, fairly strong armor and more. Defeating three bosses activates the Core at the base, and it is said that if the player keeps offering up the souls of bosses, it will eventually send them back to the surface.

Since the base was getting cramped, the player separates the workshop from the storage area and also prepares a guest room for merchants. Merchants stock rare consumables, so the narrator says they will probably end up buying them every time new stock comes in.

After that, the player digs south from the base and reaches the forest area. With new ore mined in the forest area, the player upgrades their gear from iron, and also builds a boat on the grounds that it should be useful in a water area in the future.

Locating the next boss requires 10 feathers. Feathers can occasionally be found lying around the forest area, but the narrator complains, "These are way too hard to see." After somehow collecting 10, the boss turns out to be closer than expected.

This boss needs to be lured out with bait, and the battle begins when a sparkly egg is placed. It is a type that attacks with pillars of light, and the fight is said to be fairly action-heavy. The recently obtained fire staff performed well. On the other hand, there is a mechanic where the boss's HP recovers if the ore that appears periodically is left alone, so the player breaks it with a hand drill picked up in the forest. After being fully healed several times, the player figures out the gimmick and defeats it. The rewards are an item that attracts a fishing merchant and a new pickaxe, and upon returning to base, the location of the ocean area is reflected on the map.

Taking the boat, the player heads to the ocean in the northeast, explores ruins and finds a beach house, then returns home for a while. Judging that the ocean area will be quite a lot of work, the narrator focuses on improving the base for some time.

A lot is done during this base improvement. The player expands the fields to improve meals, fixes up the base's bland interior, and organizes the storage so it is easier to understand. In addition, the player pushes forward with automating tasks, as follows:

• Automated watering with sprinklers
• Automated slime hunting with traps
• Automated ore mining with electric drills
• Set up an automated tree-felling station

On top of that, the player decorates with plants, catches pill bugs and raises them by feeding them insects, and sets up a ranch next door. By combining traps, the player also automates the gathering of mushrooms that serve as sheep feed.

After finishing organizing the base, the player sets sail on the ocean and soon finds a deposit of new ore. The player sets it up for automatic mining with electric drills and places a portal next to it so they can warp there from the base at any time.

The player visits three ocean ruins to gather weapon materials and crafts the Phantom Spark, which the narrator calls the strongest ranged weapon. Searching for the materials reportedly took several hours. Since the boss's location had already been found, the player prepares the battlefield with platforms before taking it on, whittling it down little by little with the Phantom Spark's damage and defeating it.

Next, the player heads to the desert area in the west. They collect ancient armor in the ruins, raise their crafting skill to make rare combat accessories, start mining the desert's new ore, and scan for the boss's location. The narrator says the desert may have been considerably easier compared with the ocean, while also noting that this was because the ocean was too vast.

This time, the player uses a build focused on critical hits, lures the boss out with an item, and then simply attacks relentlessly with a knife. At this stage the boss's health is quite high, and the player only manages to defeat it after attacking for about five minutes. The narrator feels it may be tough going unless they boost damage more with food, and says they will work on improving their meals once they get back.

The player expands the south side of the base and builds fishing ponds in order to try their hand at fishing. The ponds recreate the atmosphere of each area; the player first catches dozens of fish at the starting-area pond to obtain fishing gear, then gets more fishing gear at another pond. In this way, the player collects gear while also stocking up on fish for boss fights.

To build more new fishing ponds, the player brings back floor tiles and water from the crystal area and the lava area, and sets up two new ponds. At the crystal pond, the player obtains a full set of ninja gear, which the narrator says is the strongest gear available at this point, and at the lava pond, a large number of delicious fish are caught. By the time all the fishing was done, the player's fishing skill had risen from 0 to 50.

Boosting attack power with dishes made from the fish they caught, the player challenges the boss of the lava zone. Thanks to the effect of the fish dishes, damage from the floor is also nullified, and with the help of the fishing results, the player defeats it. The reward is a pickaxe recipe, which it seems can be crafted once 100 gems are collected.

Landing on the remote area that had been left until last, the player finds spots where ore can be mined, crystals that spew radiation, machines that fire missiles and more, and the narrator is delighted, calling it "the best." The player also finds alien tech ruins and obtains a destruction beam from a chest. Watching the beam break through walls, the narrator says they may have gotten themselves a nice toy. In a circular arena, a series of battles against small fry begins, and the fight ends after holding out in the center for a while.

Using the item that calls a merchant, the player summons the merchant and buys an item to lure out a boss. Scanning for the last boss's location shows that it seems to be swimming in the ocean. After a moment where the narrator resets with "Let's forget that just happened," the player buys the item that summons the boss, places the bait pillar, and starts the battle after moving a sufficient distance away.

Attacks only seem to get through the gaps in this boss's body, and the Phantom Spark reportedly came in handy for the first time in a while. After whittling it down for a while, it splits into two and then into three, but the player defeats them and wins, finishing off all the bosses.

Finally, looking back over the map of the explored area, the narrator says the ocean exploration was indeed the toughest part. In the end, they still haven't returned to the surface, but since they were able to enjoy building the base and can eat as much delicious food as they like, the narrator concludes by saying they will live here for a while.