In the Pumpkin Moon event there are enemy hellhounds that you can kill to progress in the event. The event is optional and not required to progress in the game.
Also you can get a dog as a town npc and enemies can kill it.
It's heavily implied that the Mechanic was abused by the Clothier while he was carrying Skeletron's curse, and the former does NOT forgive the latter for it.
It is implied that you can hurt "critters" (animals that can be caught with a bug net) while they are in your inventory, however an accessory can be bought from the zoologist to prevent this.
While a cat NPC can be attacked, it has a trait shared with the child NPCs where it will simply run from the world when at 0 health, rather than dying.
Similarly to children NPCS and the town slimes, the pets obtained via town license will leave the town rather than dying.
The message that displays is “[NAME] has left” and a new pet will move in after a small delay!
There is a structure/small mini-biome that can sometimes appear in the cavern level (underground), that is a spider nest. Spider enemies frequently spawn in and near these. There is also a dangerous biome that may sometimes spawn in worlds called The Crimson, that has spider enemies that spawn in it.
No but sexual harassment is alluded to upsettingly frequently in a number of instances in some npc dialogue (ex tax collector). It's not very tactful but it also isn't shown directly I guess.
There are many bladed weapons in the game. The Stylist uses scissors to defend herself, and will verbally threaten you with them and a razor on Blood Moons.
There are a couple of bosses who specifically have hands you can attack. One is a skeleton boss whose hands fall apart and stay on the ground for a few moments after being destroyed, or if the boss is killed. The other has an eyeball in each hand which leaves an empty socket after doing enough damage to them, though the hands themselves remain intact otherwise. Both bosses are required to fight in order to beat the game.
If the "Blood and Gore" setting is enabled (which it is by default), NPCs, the player, and most enemies and passive creatures' heads and other body parts fly off of their body on death. This doesn't happen if the setting is disabled. Also, when a player dies, a random death message will appear in the game's chat, many of which mention the player's head being removed in some way. These death messages can't be disabled without mods or resource packs.
Sometimes when the player dies there is a message about their limbs being ripped off. Additionally, one of the common weapons is a dismembered zombie arm.
There is gore whenever you kill most enemies with pixelated blood and severed parts but it's extremely unrealistic with the graphical style in mind and it disappears fairly quickly. Gore can be toggled off if you have an issue with it at all, though.
The only child NPC, the Angler, cannot be killed, and when he takes enough damage to ""kill" him, he simply disappears in a puff of smoke, and the text is "[Angler name] has left".
No self-sacrifice, but you can throw voodoo dolls into pits of lava and the respective character will die. One such sacrifice is essential to game progression, though a replacement for them will spawn within a few days.
"When you are ready to challenge the keeper of the underworld, you will have to make a living sacrifice. Everything you need for it can be found in the underworld." -The person who you sacrifice
The medic and arms dealer NPCs are heavily implied to be in a relationship and the arms dealer frequently flirts with other female NPCs according to dialogue, though it can easily be interpreted as them just being in an open relationship.
No proper jumpscares, but some monsters may take players by surprise. In particular, the Guardian in the dungeon, and the Nymph disguised as a friendly NPC in caves. Explosives traps underground are also very surprising.
At the beginning of the game, there is an old man ouside of the dungeon who is under a curse, and says that the player needs to free him of his curse to enter.
Interacting with him at night will summon the skeletron boss.
When it is defeated, he will be free of the curse, so its kinda like possession.
There are giant beehives made up of hive blocks, which have a lot of clustered holes in them, and the Queen Bee boss also has a cluster of holes on her abdomen which is visible for nearly the entire fight. The boss is optional, but can potentially be summoned on accident, and it's very unlikely to go through the whole game without coming across a beehive.
A whoopee cushion item can be obtained which makes a farting noise when used. It can additionally be used in the crafting of an item which makes said noise when the player jumps, although other items feature the mechanical benefit without the noise.
There are some enemies named things like "Devourer" and "Man Eater" which the player can be killed by, but no one is actually visibly eaten. There's also the Crimson biome, which is semi-canonically a living being, whose cave entrances are designed to look somewhat like mouths with sharp teeth. It doesn't actually "eat" anyone, but it may be worth mentioning here anyways.
A temple can be found in the jungle as part of the game's main progression. Players can interact with the temple however they wish, though will likely end up breaking ancient vases and traps on their way to fight the golem inside the temple.
The only person that can self harm is you.
If you die, a grave spawns. When enough graves are close to each other they make a graveyard biome.
This can cause the player to repeatedly kill themselves to form the biome for its exclusive items.
Not sure if this counts, but final bits of progression towards the final boss the chat fills with messages referencing mental numbing, reality falling apart, etc.
Possibly - drinking a potion makes a "gulp" sound effect, and eating food and using certain other items makes a "crunch" sound, like someone eating a potato chip. The sounds are less than a second long, but you're likely to hear them fairly frequently, especially the "gulp" sound.
A major component of the game is underground exploration, and there are many small caves, holes, and passages. Additionally, it is possible to die from suffocation if blocks like sand fall on top of the player and bury them.
Graveyard biomes spawn when enough graves are near each other. Graves appear when a player dies.
This can encourage the player to kill themselves multiple times in order to form the biome and get its items.
There is no cannon suicide of any NPC and the biome is not required to progress to suicide is optional.
Water is present throughout the world, and it is unlikely that a player could complete the game without once entering water. Being underwater too long will make the player take damage, eventually killing them. Some items exist to mitigate or nullify this behavior.
There are no n-words.
However there is anti-blackness in the game in general:
1. The Witch Doctor's character as a whole. 2. The Arms Dealer speaks in stereotypical AAVE and sells guns to you and has shady illegal practices (he can sell you "illegal gun parts"). NPC names are chosen from a list of which the Arms Dealer's names are all common black American names. 3. The Zoologist is the Golfer's (who is a black man) sister, and she is portrayed as an animal/werewolf-esque character...
There is a enemy race of reptilian lizard people who have a golem (a protective and good creature that originates in Jewish folklore) to protect them.
There are also hostile enemy golem in the mine, and one of the game's biggest bosses is a golem.
Some of the merchants can have Jewish names.
There are goblins in the game.
The game simultaneously has nazar amulet as a protective item...so...
Characters created before a binary gender option was introduced were all set to "male", and so all of these characters are treated as men. This is not as issue for newer characters. However, there is no gender neutral option in character creation, only male or female.
A little - there are cultist enemies near the end who worship the final boss, and there's some items associated with various real world religions, like the Cross Necklace, Ankh Charm, and Nazar. There's also a Christmas event, but it doesn't mention any of the explicitly religious aspects of the holiday.
While most NPCs require an available home before appearing, the guide, angler, tavernkeep, mechanic, wizard, and goblin tinkerer will appear in the world randomly, wandering around until a home is made available.
Since the time the above comment was made, there IS an "epilogue" of sorts shown in snippets during a credit sequence. However, it is basically shown that the world has improved and the NPCs are living better lives thanks to you, so I'd say it's a happy ending.
There is a biome called The Crimson thaf is blood-themed. There is a boss in this biome that is a large brain. There is a boss that is a giant eyeball (with bloody bits hanging from its back). There is a boss that is a giant wall of flesh featuring eyeballs. However, all art in this game is pixel art, and thus there is no "real life" gore. There also can be pixellated blood when something dies, but there is an option to turn this off in settings.
Also you can get a dog as a town npc and enemies can kill it.