I finally made it to the center of the my first planet. However, thinking I was gonna find anything, apparently their is a limit as too how far deep you can go. The core had nothing but lava (duh), and making a long tunnel system using stone bricks for the walls, and dirt to fill up the lava space, I was hoping to find some sort of boss or hidden temple. Of course this was in Alpha Sector, LVL 1 planet, and I do not know anything in the wiki that says there might be something at any planet's core. But if not, I would like to argue about possibly a mob or boss in every planet's core. Since the core of the planet is just a underground side scrolling river of lava, it would make sense that the creature "swims" in the lava in a serpentine pattern, similar to a Chinese dragon dance, except it is actually a giant worm-like creature capable of surviving such harsh temperatures, and yes perhaps a cross between a Tremor if you recall the famous Sci-Fi movie series. How the body is composed in regards to in-game mechanics should be sections that pivot, turn, and overlap depending on where the head moves and the rest follows. Of course, to make the game more exciting and challenging, the creature should have the capability like a Tremor to drill or dig through any constructed obstacle, with an exception of relative difficulty with lava rock. This will engage in the player's creative, resourceful, and survival mentality aside from just running around and shooting things. And with that being said, with such a difficult should come great reward. Perhaps a high tier weapon, or an ingredient to crafting one? Perhaps a new set of armor plating crafted from its thick exoskeleton? Of course, like the mob variance in look, size, etc, of Starbound, the Tremors could look different in regards to color, thickness, and even length (so more sections). Also, it should be a rare spawn and perhaps one or two in each planet's core, continuously moving where it wants relative to the lava. Aside from looks, movement, and drop items, its attacks should be fairly simple, it drills through whatever it is that you make as to prevent lava from flowing through (if you happen to already be in the core), and perhaps spew whatever it is from the mouth, perhaps fire bursts, acid, flames, or anything. It should differ from planet to planet, and definitely in biomes where lava is abundant. It's health should vary but should be greater than or at least as strong as the 2-3rd boss, and damage it can deal should almost take out 2/3 health of a naked player LVL 1. As for the additional fluff like lore, possibly finding such accounts or logs in villages. Also, maybe a different boss aside from this can be implemented to be unique to each biome and planets core. I was also thinking of a side scrolling Titan, just from the waist up that side scrolls the planets core similar to the wall of flesh from Terraria, as well as an amoeba like lava monster. But I have to think about those firsts before I can detail them on another comment. Sorry for the lack of organization and a sketch for my comment. This is kinda last minute for me. I will provide some drawing eventually.