Old biomes will shine anew with Red's Structures addon that fills the world with new buildings. Players are incentivized to explore forgotten towers, houses, and temples with loot chests. All of the generated structures contain loot, but be aware of the dangers you might encounter while exploring them. Generated constructions may vary between biomes, so it makes sense to visit all of them.
As of now, more than eighteen structures will be changing the face of Minecraft's world. For some of you, the spawn rates may be of concern, like towers appearing too often. But for me, I like it that way because there's always something to be excited about over the next hill.
Credits: redstonegames
Oracle of the Plain
Jungle Pyramid
Sawmill
Dark Tower
Small Buddha
Big Buddha
Don't forget to activate Experimental gameplay options.