My pick will definitely be Black Sabbath's first 6 albums. They were incredibly important, influential, defining but most of all they were all very different from each other (inside the respective genre), coherent, creative and filled to the brim with incredible all time riffs and performances... And just insane songs overall, the amount of great material is absurd.
Black Sabbath, Paranoid, Master of Reality, Vol. 4, Sabbath Bloody Sabbath and Sabotage.
Radiohead.
Every single album has been an improvement of the one before, drastically changing direction and challenging listener expectations.
Smashing Pumpkins, Gish - Adore. Including B-Sides and compilation albums I can’t think of another band of that stature who were as prolific, wide-ranging and consistent.
Dark Side of The Moon
Wish You Were Here
Animals
The Wall
The Beatles... not sure anyone comes close.
The White Stripes went 6 for 6.
Rubber Soul - Revolver - Sgt. Pepper’s Lonely Hearts Club Band
Nirvana
Metallica- Kill Em All through the Black Album.
System of a down
Imho they took a hard dive with everything following Machina
RHCP, start to finish
It might be a cliche answer but The Beatles were absolutely but unstoppable from Help to Let It Be