[6] Adam Jones recalls a story in which the band purchased two second-hand pianos with the intention of blasting them with shotguns in the indoor parking lot of Grand Master Studio and putting the resulting sounds to tape.

[8] This version of the album included a note from the band: It came to our attention recently that many stores across our fine and open minded nation would not stock Undertow because of our explicit artwork.

AllMusic gave the album a positive review, stating "With its technical brilliance, musical complexities, and aggressive overtones, Undertow not only paved the way for several bands to break through to the mainstream adolescent mall-rage demographic, it also proved that metal could be simultaneously intelligent, emotional, and brutal.

What put this L.A. band a notch above the rest are better songs (with actual verses, choruses, and hooks-check out the terrific "Prison Sex") and the hints of vulnerability in singer Maynard James Keenan's voice".

Searching, angry, liberating and scary, Tool's full-length debut emerged during a period in rock music when Seattle bands like Nirvana and Pearl Jam were expressing alienation through grunge riffs, inspiring lots of copycat artists.

Undertow expressed alienation, too, but the album's imposing waves of misery and dread seemed to come from an entirely different planet than grunge, providing a startling counterpoint to the trendy sounds of the era".

[11] A less positive review came from Select writer Andrew Perry, who said "[B]ereft of the irony, danger and maverick punkiness of grunge's finest, Tool ultimately will only help Alice In Chains reassert the trad metal market.