Terraria has some impressive pixel art. Every sprite in the game is excellently crafted and looks brilliant when on screen. It truly is art and how fitting that the game itself contains a multitude of pixel art pieces which you can hang on your in-game wall. These paintings come in all shapes and sizes and can be found in a variety of places.
The Golfer is an NPC related to the Golf minigame added in the Journey’s End update. You can find him in the Underground Desert biome and talking to him will cause him to move into any unoccupied valid housing in the world.
All paintings sold by him are effectively rewards for doing well in the Golf minigame, not appearing in his shop until you score at least 2000 points in Golf.
The Painter is an NPC who sells various paints which can be used to color blocks for more appealing builds. He arrives in your world after you have at least eight other town NPCs (four on 3DS). Depending on the biome he’s in he will sell different paintings.
The Painter has a large number of unique paintings that are sold while he is in a Graveyard Biome. The Graveyard Biome is a player-made biome and can be created by having at least seven (six on mobile) Tombstones of any type near the player. You’ll know you’ve made the biome when the colors become desaturated and a mist covers the ground. The paintings have no other requirement other than the Painter being in the biome so they will all be available for purchase at once.
The Princess is one of the most hard to get NPCs in the game as she requires every other town NPC (excluding the Santa Claus NPC) to be in your world. When she does move in, she will have these paintings to sell.
The Travelling Merchant is a unique NPC as he doesn’t require housing, leaves after a period of time, and changes his inventory daily. He will begin to appear in your world after you have at least two town NPCs and will have paintings in his inventory on rare occasions.
Underground Cabins are the ruins of once-existing living spaces that you can find as you explore the caves of your Terraria world. Each biome that has an underground variant at world generation has a special Cabin associated with it. These biomes include the Underground, the Glowing Mushroom Biome, the Ice Biome, the Jungle, the Desert, Granite Caves, and Marble Caves. Paintings can be found in these Cabins on occasion and are the only way to find certain paintings.
Desert Underground Cabins aren’t particularly unique to any other biome’s Cabins other than having a higher chance to have the Extractinator item and being the only place to find certain paintings.
The Dungeon is a massive structure near the Ocean on one side of the world. It will always be on the opposite side to the Jungle Biome and is guarded by the Dungeon Guardian and Skeletron. After defeating Skeletron the Guardian goes away and you can explore the deeper Dungeon. On the walls of the Dungeon are a variety of paintings only found there.
The Underworld (sometimes called ‘Hell’) is a biome at the very bottom of the world and spans the entire length of the world. In this biome there are broken down obsidian structures that house miscellaneous Obsidian furniture, Hellforges, and Underworld-exclusive paintings.
Goodie Bags are random drops which occur only during Halloween. They can drop from any enemy and can be opened by right clicking on them in the inventory. When opened they will give the player a random prize like a vanity set or a painting.
The Angler is an NPC who gives the player fishing quests where they have to fish up a special quest fish and return it to the Angler. The Angler can be found at either Ocean and will move into unoccupied valid housing after being spoken to. One of the rewards for his fishing quests is a painting.
All NPCs can actually occupy houses in a Graveyard Biome. They will even complain about being there when you talk to them, however it doesn’t actually affect their happiness.
Goodie Bags can be dropped by any enemy during Halloween so if you have a place to farm already use that. If you don’t you should use events like the Goblin Army and the Slime Rain to kill lots of enemies for more chances to get them.