Pugstorm and Re-Logic have announced a Core Keeper Terraria crossover. Both games will be getting content themed around the other, so you'll be able to take on a fearsome Terraria monster in Core Keeper and befriend a cute little Core Keeper critter in Terraria.
What form will this Core Keeper Terraria crossover take?
Since Core Keeper and Terraria are not a million miles away from one another thematically, a Core Keeper Terraria crossover seems like a (re-)logical step, and that's exactly what you're getting next week. It's being added to Core Keeper on September 26th, so you won't need to wait for the November update to check out the crossover. Terraria gets its Core Keeper fix alongside its 1.4.4 update on September 28th.
According to Core Keeper studio Pugstorm on Steam, the Core Keeper Terraria crossover is coming to both games next week, arriving in Terraria a couple of days after Core Keeper. In Core Keeper, the crossover means you'll be able to summon and battle Terraria's King Slime. Battling him could net you some pretty sweet loot, although Pugstorm is remaining tight-lipped regarding what that loot is right now.

What about Terraria Core Keeper content?
In Terraria, meanwhile, you'll be getting the chance to domesticate your very own Caveling. The Caveling Pet will follow you around and "[offer] a little moral support wherever you go". The item used to summon the Caveling Pet will be a recognizable one from Core Keeper, but again, Pugstorm isn't giving anything away just yet. How mysterious!
As Pugstorm says, this crossover is coming as part of a wider Terraria update that's on the way next week as well. The Terraria 1.4.4 update is adding a whole bunch of stuff to the sandbox building game, including new items, seeds, and lots more. Even though it constantly seems like Re-Logic is saying it's done with Terraria, it seems that the game isn't going away just yet, which is good news if you're still immersed in its 2D pixel world.
The Core Keeper Terraria crossover content arrives in Core Keeper on September 26th and Terraria on September 28th, so make sure to look out for it then. In the meantime, why not take a look at our Core Keeper guides to get you familiarized with the game's hostile yet compelling world?