MythiTech

13 mods including:

Biomes O' Plenty

Buildcraft

MrCrayfish Furniture Mod

Galacticraft

Not Enough Items

Natura

Natural Baby Animals

Pam's Harvestcraft

Portal Gun

Quark

Sanity Mod

Tinkerer's Construct

and Zombie Awarness.

Biomes O' Plenty is an exploration mod, adding 80 biomes and 12 subbiomes, as well as new ores.
Buildcraft is an automation mod, adding machines to mine for you, and other random things.
MrCrayfish's Furniture Mod adds furnitures such as tables, chairs, curtains, beds, and many many more thingies.

Galactricraft is a space exploration mod, allowing you to blast off to other planets and moons, and explore the many creatures and blocks that are there.

Not Enough Items is a simple inventory recipe book, as well as a cheat screen. Cheating isn't required!

Natura is a world generation mod, adding lots of new trees and plants, and makes the Nether a lot more challenging.

Natural Baby Animals makes baby animals spawn naturally out in the wild. A feature Minecraft has been missing for some time.

Pam's Harvestcraft adds many new plants and food items, like Zucchini, and Pizza!

The Portal Gun mod adds a portal gun into Minecraft. And if you don't know what a Portal Gun is, 1, I'm going to find you, 2, it fires portals onto surfaces that bend space, to travel instantaneously between two points, that may be billions of miles apart if you wish.

Quark is a simple mod that basically adds everything missing from Minecraft, including Emotes, Redstone items, and blocks.

The Sanity Mod adds a mental health state into Minecraft. Killing animals and eating bad food lowers your mental state. Eating good foods raise your mental state. If your mental state is too low, you will begin to hallucinate.

Tinkerer's Construct is a smithing mod, giving you the ability to create all forms of weapons and tools. Ever wanted an obsidian sword with an emerald hilt? No? Well you can make one anyway.

And last, but not least, the Zombie Awareness mod makes undead mobs smarter. They can detect your presence based on light sources, and blood, and have better pathfinding code.