(I updated the review for the 1.4 patch and the Minecraft 1.16 patch. This is the best game ever.)

This is my new favorite game.
Some people think it's just Minecraft 2D, but I think it's Minecraft 2.0.

First of all, there are tons of quality of life features. Most notably, the ability to quick stack your inventory into any chests around you, allowing you to make storage rooms that only require you to zip through and clean out your inventory instantly. You have the ability to make one character that can go to multiple worlds and even servers, as well as one world that can be visited by multiple characters. In Terraria, worlds and characters are independent, meaning theoretically all items in the entire Terraria community are linked. Back to quick stacking, you also have the ability to favorite items you want to keep on you, so you never have to worry about losing or misplacing your gear. Separate vanity slots make designing your character less limited. You really can't tell what a person is wearing based on what they look like in this game. Smart cursor allows you to dig and, in some cases, build without much effort as you only have to put your cursor in the general direction you want to build towards. Auto select allows you to perform advanced actions while barely thinking. Pylons allow you to teleport to any biome in your world once you unlock them.
In Minecraft, biomes are always based on the world seed (In singleplayer worlds, they can be manipulated on servers.) and cannot be changed. However, in Terraria, biomes are based on the blocks found in your area. You can actually change the biome in a particular area by placing enough of one particular biome block (such as snow blocks to make a taiga or sand to create a desert).

Another reason I like Terraria more than Minecraft is the immense amount of content they pack into a $10 package.
In Minecraft, there are 361 unique items. However, in Terraria there are 5044 items.
In Minecraft, all tools can be used as weapons, and there are 5 tiers of tools, from worst to best. However, in Terraria, there are 387 weapons split into 4 major classes to choose from; no one sword or armor is the absolute best in the game. Some tools can also deal damage, but less so than actual weapons.
In Minecraft, there are a few mounts, a minecart, and a boat, but in Terraria, there are 26 mounts (of all kinds), and 25 minecarts, and many ways to tackle traversing water.
In Minecraft, there are 7 unique ores you can mine in caves, but in Terraria, there are 21 ores, some of which are in caves, but others can be obtained by fighting bosses, opening crates, or unlocking them through progression.
In Minecraft, there are 37 mobs, but in Terraria, there are 438.
In Minecraft, there are 2 bosses, 1 mini boss, and 1 event, but in Terraria, there are 17 bosses, 14 mini bosses and 19 events.
Terraria also has furniture, NPCs, and, because of Steam integrated multiplayer, you can play with friends even if they aren't on the same network.

(Source: "Minecraft Info")

One other thing I would also like to comment on this game is the graphics. This game uses retro textures as its main style, and this is the best attempt at that style of graphics I've seen in a while. In the old days of Terraria that I never played because I'm not that old, the graphics are lacking compared to today and especially 1.4, but right now, especially right now, the animations and appearance of this game is amazing. The lighting is one aspect of it. Lights can glow in any color depending on the source, and they can change the aura of their surroundings, making them an important part of any build attempt. Blocks can mix with themselves in realistic ways and even other block types sometimes, and walls snap to surfaces and furniture items in ways that really make sense. Blocks can also be sloped and painted, and so can walls, making the possibilities in buildings truly endless, as if the sheer block choice wasn't already impressive. And the way these blocks are textured and rendered along with the general design of the game is very impressive, and is downright awe-inspiring. Even procedurally generated terrain is inspiring to look at. Weapons, armors, and hell, even vanity and dyes and enemy models can emit light and are textured along with their biomes and the game itself, and I can't help but be completely struck by watching underground skirmishes with all the colors and projectiles flashing across the screen. I am the kind of person who likes to put effort into making things look good, and I think the devs agree.

Many people look down on Terraria because it was inspired by Minecraft, some details of the game being directly stolen from Minecraft, and while that is true, Terraria is so much more than a ripoff of Minecraft.

Overall, the content is amazing, the quality of life is almost too good, and the soundtrack makes me want to leave it on the title screen for hours.

Please, buy this game for the sake of humanity.