The Internet has long delighted in bizarre mash-ups and nineties kitsch, in many cases to the point of cliche. Somehow, Neil Cicierega has driven both to a new level of weird with his mixtape Mouth Sounds and its “prequel,” Mouth Silence.

Cicierega–best known for his YouTube series “Potter Puppet Pals”– has previously released nine albums under the name Lemon Demon, but the Mouth Duology is a new career highlight for the online creator. It takes either audacity or insanity to smush “Billie Jean” and “Smells Like Teen Spirit” into the same track and Cicierega posses an equal amount of both.

Songs are tossed together with little regard for quality or similarity: Santana duels Enya, “You Oughta Know” bumps into the theme from Full House, and “Tubthumping” wrestles Third Eye Blind for Mouth Silence’s finale. The resulting whole is a dense swirl of sound, sporting multiple twists per track.

Cicierega’s work has frequently featured a knowing parody of nineties nostalgia, but his pet subject reaches a new excess on these mixtapes. At least half of the samples have been mined from that decade and it becomes tough to determine if the artist’s obsession is sentimental or sarcastic. A similar air of smug humor surrounds the entire project: Cicierega describes the albums as taking place in an alternate universe where “music is able to fluidly cross time barriers” and the gags in the track listing–such as matching “It’s the End of the World as We Know It” with the other rapid list song of the eighties, “We Didn’t Start the Fire”–betray a reservoir of pop culture savvy.  Cicierega’s tone makes it difficult for a listener to embrace his releases without feeling like a joke is being made at their expense.

It’s difficult to say if the mixtapes are actually good or if the listener, unable to look away from a musical trainwreck, is set under a kind of Stockholm syndrome. But the best combinations–a series of Pokémon news reports set to “I Want You Back,” Smash Mouth grafted to Modest Mouse’s “Float On,” Elton John backing System Of A Down–feel oddly inspired, while the production is often thoughtful and intricate. The more time spent with Cicierega’s creation, the more it begins to make a strange kind of sense.

While the twin releases each feature a fair number of highlights, the first installment is dragged down by an overreliance on Smash Mouth’s “All Star,” a joke that wears thin on relistens. Mouth Silence’s (even more) eclectic sources and lack of a real “concept”  ultimately prove more enjoyable.

Both mixtapes can be downloaded for free from the artist’s website at www.neilcic.com