"When the Levee Breaks" is just an incredible piece of music, from the heavy opening drum beat to Plant's wailing vocals near the end. Pure blues. Sure, they didn't write that song, but they made it their own.

"Kashmir" just feels like the pinnacle of what Zeppelin was able to achieve in a studio. Again with a heavy opening drum beat and Jimmy Page's riff to the horns and strings, and Plant's vocals.

For whatever reason, I feel like both those songs will be going through my head nonstop when the zombie apocalypse breaks out. There's just a crazy kind of mood that they evoke.