7 Days to Die is a voxel based survival horror game that focuses on crafting and world building, all while having you take a hand at surviving in an undead filled post-apocalyptic world.
Pro What you build is not only for creativity, but also for gameplay purposes
In 7DTD players don't build their homes only as bases or places to sleep in, or build cool looking things just for the fun of it and to test their skills.
Every 7 days, a large horde of zombies will attack the player wherever he or she is, trying to destroy them and what stands in the way of the player and the horde. This is why the player needs to think about how to build traps that will help them kill a lot of zombies and how to make a strong enough house that will not be destroyed easily.
Pro Great replayability
No matter how many times you start a new game (random gen) you will never get the same experience. The crafting is the same, enemies are the same, game mechanics are the same but the gameplay is not. If you add the mods available for this game then you will have a whole new experience with added/altered crafting, different enemies, more quests etc...
Pro Thoughtful and communicative developers allows for a stable community that keeps growing
Even though this is not directly related with the gameplay, it's still important especially for indie and early-access games. The developers behind 7DTD have always been communicative and have heard what the community had to say time and time again, releasing patches with bug fixes and new features in a timely manner.
Pro Randomly generated open worlds makes for a ton of replayability, as each playthrough is never the same
Recently added in the Alpha 9 release, randomly generated worlds allow the player a new play experience every time they open up the game. This means every server will have a different dynamic based on their layout of the world.
Pro Unique combination of voxel and polygon models, which makes for pretty fun physics
The game is a mix between a voxel world and full polygon models for buildings, making for a versatile survival based world that brings exploration and creation to the zombie survival genre.
Structural integrity is a real thing in 7 Days To Die. That means there cannot be unsupported floating blocks. The player can set up traps to take out hordes of zombies with a falling building.
Weapons will break and crumble but can also be forged to be awesome, and food will spoil so the player must cook and maintain supplies.
Pro Single, co-op, and multiplayer gameplay modes give plenty of choice as to how one would like to tackle the game
Three different play modes including solo, with friends, or competitively over the internet gives a lot of choice as to how someone would like to play the game. Be it with friends or solo, the options are there.
Pro Constant sense of vulnerability, which keeps the player alert and on edge the whole time
As the player makes progress in the game by interacting with the environment, killing zombies or building things, they are rewarded with skill points that can be used to unlock new skills such as combat strength, higher stamina or new crafting options.
But even though the skill system can seemingly make the game easier, the severity and size of the zombie hordes will keep increasing with the time spent in game and the progress made by the player, keeping them on the edge and making them feel a constant pressure that an attack may come at any time and that they should be prepared.
Con Crafting system is constantly getting dumbed down
Even though 7D2D is supposed to be a hard survival game (and most of the time it is), the crafting system is getting constantly dumbed down with new releases.
For example, previously you had sticks, planks, and logs. Sticks could not be used to build huge wood log walls or frames. While now there's no more different kinds of wood and you simply punch a bush to get some wood.
Con Randomly generated open worlds has no generation options
Randomly gen has no option to customize how it is generated (like in minecraft for example) and could make it quite problematic if you want to have a good map, as there is no way to know how good or bad the map will be. Random gen also make unrealistic hills and road that almost go up/down vertically with vehicle spawning in such way they seems to be floating.