[Certain]

I see a really strong parallel between OutKast and Radiohead, probably my favorite groups of their era.

Pablo Honey : Southernplayalisticadillacmuzik
The album that started it all but sounds a bit unadventurous, sloppy and unrefined in retrospect and mostly is remembered for one huge hit that some fans of the group deride.

The Bends : ATLiens
A pretty much perfect album end to end that definitely foreshadowed the risks coming without actually diving headfirst into them.

OK Computer : Aquemini
Everything gets thrown out onto the table, and even though it's not as perfect and polished as the previous one, the exploration makes every note fascinating.

Kid A : Stankonia
The album that takes the previous one and furthers those steps all the way off the cliff, making for a fascinating but at times ungrounded listen.

Amnesiac : The Love Below
Everything that made the previous album so weird is pushed all the way to the fore, and the last remnants of the original sound are kicked out entirely.

Hail to the Thief : Speakerboxxx
A return of sorts to the 1990s core, with greater roots in established music while not at all skimping on the experimentation, but somewhat underrated because it no longer feels like genius.