I have a question. If you put your Minecraft/forum username down as the seed for a new world, what does the world look like?
Well, here's mine! This is using the seed "Avyn" with a capital A, and that's it.
Here's spawn. Oh, boy. A savanna biome right next to a plains. My two least favorite biomes. Joy.
So I take a little fly backwards to see the bigger picture, and I'm feeling a lot better about this. There's a knobby sand dune mountain thing in a desert just right there--a desert! very useful--and I'm right next to the ocean. It's actually a pretty pleasing little island/peninsula/thing.
By going just a little further south, I see the cutest little tiniest forest I've ever seen! Look at this thing, it's adorable! I do see a mountain range off in the distance--my favorite biome--so maybe there's hope for this seed yet.
That's seed Avyn! Not what I was hoping for, I must admit. It would be a useful survival world, though. Lots of flat space to build, a variety of wood at your fingertips, and a desert for infinite sand!
That's a nice seed. Savanna's, plains, and deserts are great starting biomes. They have very good visibility, are easy to traverse, and can spawn a lot of animals and monsters.
Mine is AstralMagic. It is highly unremarkable.
The spawn point is your ordinary Minecraft forest.
To the north there is a taiga with two mountains visible in the distance
To the southwest there is another mountain, and some plains a bit west of that.
There's a snowy taiga to the east, and a tundra to the southeast.
As I was uploading this I realized I could have used Optifine to get a better view of my surroundings, but I'm too lazy to go back and redo the screenshots. If there's anything of interest in the distance it'll remain a mystery.
This is what "TheMasterCaver" gives you in the latest version of my namesake mod:
View from spawn, which is in a Bushlands biome with Savanna Mountains to the east and Mega Tree Plains and Ice Plains to the west
Traveling eastwards, I came across the following biomes and terrain:
A Rocky Mountains biome, which is basically a mountain the size of an entire biome, with the highest peak reaching y=167:
A vanilla Mega Taiga biome, one of 3 variants of "Mega Taiga" biomes, including one of my own design:
They don't call them "Extreme" Hills for nothing; this one reaches y=186, near the maximum height of terrain in TMCW (y=192):
Further east I came across a small village at 600, 230 next to a TMCW Mega Taiga biome, with huge spruce trees with 3x3 trunks (this was my original "Mega Taiga" biome that I added in the first version, with the vanilla 1.7 variants added later):
The underground is just as interesting; these were the largest caves that I found:
This cave, at -264, 840, has a volume of about 360,000 air blocks, which is still not the largest they can get (I found one with 685,000 in a different seed):
A massive ravine at -648, 584 going all the way from the surface to lava level, 59 blocks below sea level, and so long it isn't possible to see from end-to-end, and has a volume of about 250,000 air blocks:
An intersection of two large ravines near -20, 985:
A giant circular room at -84, -556 (a much larger version of the "rooms" found in vanilla):
Another large cave, part of a complex of several nearby, with a literal lava sea:
Here is a biome map, made with my own mapping tool (2048x2048 blocks centered at 0,0 with a 256x256 grid, spawn is to the west of the yellow biome at the center), an underground map, also made with my own tool (both are included with the mod, the cave mapping tool also lists the locations of all types of caves), only showing "special" cave variants (the lack of any near the center is due to a 512 block radius exclusion zone, which can be disabled with a "NoExclusion" patch), and a rendering of the world made with MCMap (unavailable for newer versions):
Also, this is what vanilla 1.6.4 gives (both of these were taken from older threads on the same subject):
Just to the south is Ice Plains:
Then I came across Extreme Hills, which while generally not as extreme as in TMCW still had some huge overhangs:
A desert temple at 170, 235 and a village at 550, -850:
Caves in vanilla 1.6.4 are still much more interesting than in 1.7 and later:
These are surface and underground renderings I made with Unmined: