Some user created content gets attention simply because it fuses two popular properties. With Minecraft those kinds of combinations are especially prevalent. It's a world-construction game, a giant playground built with the equivalent of virtual LEGO blocks where you can create tributes to your favorite universe like the Enterprise or Call of Duty maps. Other fan-service mods let you change the look of the world like, for example, the Animal Crossing texture pack, or the one for Borderlands. It's another thing entirely to do what user Gary520 did. Instead of simply reskinning items and interface or building a giant Link statue, he essentially made a Zelda game using the Minecraft mod AdventureCraft by Cryect.