I think that minecraft lacks of fantasy biomes (biomes which don't exist in real life and are inspired from fictions). In the overworld, there is only mushroom islands that put the player in a completely different environment (in which he is safe, without hostile mobs ; but in which he can't really find wood, seeds...). You could say that minecraft should be realistic, and have only biomes that exist, that make the player feel that he is exploring a real world. I totally agree with that. However, there would'nt be any impact on the basic gameplay if the biome which I'm going to speak about is extremely rare (like mushroom island for example, but even rarer would increase the challenge to find it). Let's begin.
The Giant's biome. It would be a biome where every single thing would be insanely big (a bigger version of a basic biome, like forest). Where grass (the plant, not the block) and flowers would be 4-5 times higher than the player (i know that it is hard to make a plant that covers a chunk ; it could technically be a structure, made with blocks -new blocks ?-, that gives the impression of being a grass plant/a flower). Where normal trees -new tree type ?- are even bigger than jungle trees (40-50 blocks tall -i know that more would cause to much lags, maybe don't allow leaves to decay would be better too, in order to avoid an insane amount of checking that could lag the game- and 5-8 blocks large for example). Where hills look like mountains. Where the terrain is not made for humans : jump is not enough to climb hills, because there is often 2 blocks of vertical drop; not like extreme hills where the relief is vertical, more like if you were a silverfish walking in a forest hill (if you understand what I mean).
And especially... where every mob is 8-10 blocks tall (2 times bigger than grass).
Imagine cows, pigs and sheeps beeing that tall (obviously with more health, you shouldn't be able to one shot a sheep with a sword ; and maybe they could drop more meat, or a different meat type that restores more hunger bar) ! That would be really fun to explore.
What about night ? You could think it would be impossible to kill/survive to any hostile mob. Actually not : mobs wouldn't notice your presence, small insect you would be ! Only if you attack them multiple times, they would try to attack you. That could be so scary to evolve in that biome at night, under spiders and skeletons, trying to not being see by them (maybe they could attack you in some case ? If you're staying to much time close of them ? Rarely, randomly if you are unlucky ?) ! Obviously the mob spawning mechanics would be different than the normal one, or there would be too much mobs (in every possible space). Maybe allow mob spawning only if no other mob is around 15 blocks, like this there is space beetween them ? Maybe giant mobs would have a separate mob cap, more limited ? These mob would have a "Giant" tag : it's bigger than a normal one (size) and it doesn't notice your presence, in most of cases.
What would be good would be the cave generation. It would be so nice to have such enormous caves underground (like 20 blocks of vertical space).
This biome should stand at y=80 at least, to have multiple levels of cave underground. It should also be taller (in surface area) than normal biomes, like everything is big inside (or the real space, seen from a giant would be small). However, it should be extremely rare, to increase the challenge of finding it and to avoid the problem of finding it everywhere, as it is a fantasy biome and should be researched before. However, you shouldn't ever miss it, if you're lucky enough to find it. From outside, it should be like a shock when appearing on screen, with its edge biome making the height transition.
Last but not least, there would apparently be a hidden civilization (of normal size humans) that we don't know much about who left some ruins, sometimes in caverns, sometimes inside of trees... sometimes above trees, at cloud level ! These ruins are hard to find, but they countain treasures, that you can't find anywhere else ! How did this civilization survived in such a hostile place ? You'll maybe find some of their objects, some of their tool that could maybe help you to survive... that help you to kill the Giants ? There would be some leftovers of book in which you could learn the Giant's weaknesses... this ancient civilization also knows the secret of a strange potion... but you need to explore to know their secrets ! Good luck :)
Aditionnal ideas :
- Have a snowy version of the biome, which generates in snowy regions
- Have a mutated version of the biomes (Giant, Giant Edge, Snowy Giant, Snowy Giant Edge), hillier and maybe with different trees.
If you developpers consider adding this biome to the game, feel free to add only a part of it. If you don't like X feature I'm describing, because you don't think it matches with Minecraft, tell it to me ; I have plenty of ideas that could fit with that biome, and could potentially be better.
Do vote if you think the idea is good enough to implement the Giant biome in the game ! Comment if you have any suggestion, I'm opened to hear any good addition to the biome/to its lore!
Ps : I'm not english, don't blame me if I did mistakes !
Edit (here I will post answers to the interesting comments) :
nudelholzsuppe : Cubic chunks would be problematic, because the maximum heigh is 256. So there would be only 16 "chunk blocs" heigh in the biome, which is not convenient.
LindolfoDias : Mobs ignoring our presence is a nice feature in my opinion. Because there are tall, they should almost one shot the player (and one shot if they are many on you). So a gameplay where the mobs are ignoring you could be nice, because the goal isn't to kill mobs in order to not be surrounded by the ennemy ; but it would be to be as quiet as possible, and try to run if a mob see you/try to fight him but the last option would be very difficult.
I don't want to add a giant block, because it reduces relief ; the concept of a Giant Biome is also nice because there will be more details.
VikingLemon9009 : I love the idea of having giant mobs. It would be so impressive, and the player, unlike usual, will feel powerless, until he explores the Biome and find the appropriate weapons in the ancient ruins. However I like the idea of having a new exclusive mob in this biome. It could be an extremely little thing, that constrasts with the rest.
Kaan Özkök : I don't want this biome to be a dimension, but a biome that generates in the overworld. The main part of its beauty lie in the contrast beetween it and the rest. But like I said, it would be very rare. The biome will be in the category of the mushroom island : a fantasy biome. I think that we really don't need an other dimension. The Nether and the End are already empty enough for my taste (they need an update too)
ivaniandi : A map that can help you to find the biome is a cool idea, even if currently it can only help you to find structures. However as "ancient ruins" structures are exclusive to this biome these maps could indicate the location of ruins and therefore the location of the giant biome. But I disagree with the idea of a teleporting portal because the goal of the biome is also to make the player that wants find it exploring the world
Don't forget to vote ! :D I really want this biome in a next update !