Since it premiered on Fox in 2019, the United States version of The Masked Singer has taken the world by storm. With its bizarre costumes, corny humor, and outlandish guessing game, the series is as addictive as it is fun and frequently features surprising celebrity talent behind its many masks.

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With 6 seasons aired to date, The Masked Singer has featured some truly impressive feats of costume design to go along with some likewise unbelievable celebrity appearances. But it has also been the case that many masks and celebrities both have been completely forgettable, leaving the users of Reddit with plenty of opinions about the series' most forgettable contestants to date.

Gremlin (Mickey Rourke)

Gremlin talks to Nick Cannon on The Masked Singer.

As it has progressed, the series has opened itself up to introducing contestants who are, essentially, joke contestants who cannot sing at all in contrast to the many celebrities who surprisingly sing well on The Masked Singer. Season 4 of the competition introduced viewers to the ugly-cute Gremlin, who voluntarily unmasked themselves as Mickey Rourke.

No matter how famous Rourke may be, Redditor Otterstripes had a good counterpoint about the forgettability of the character: "To be honest, I probably would've forgotten about Gremlin if he didn't outright eliminate himself." Although Rourke is an acclaimed actor with an Academy Award nomination on his CV, Gremlin was a terrible singer, and not around long enough to be remembered.

Mother Nature (Vivica A. Fox)

Mother Nature (Vivica Fox) poses on stage in The Masked Singer

The Masked Singer has aired six seasons so far, but even contestants from the most recent season have failed to leave lasting impressions on some viewers. Redditor bobthecowestboy wrote, "I already forgot about Mother Nature lol." Mother Nature was a contestant in the series' 6th season and eventually revealed to be actress Vivica A. Fox, who starred in one of Quentin Tarantino's best movies, Kill Bill.

No matter Fox's star power, much of what went wrong with Mother Nature can be attributed to the ugly costume. User JoeMomma1975 echoed this sentiment, stressing that what made Mother Nature so forgettable was a terrible costume: "I’ve only hated two costumes in the history of the US version of the show—- MN is one of them!"

Black Swan (JoJo)

The Black Swan, JoJo, poses on stage in The Masked Singer

Sometimes, utterly forgettable contestants can almost win a competition. There have been winners both worthy and not deserving on similar shows like American Idol, where the distance from past seasons allows viewers to question how certain champions ever won in the first place.

The Masked Singer viewers are already starting to question how some contestants placed as high as they did, including the Black Swan, revealed to be early 2000s pop star JoJo. That's the argument that Redditor Tiguy789 made when they wrote, "Black Swan. I don’t care that she got 2nd place." Even with a good singing voice, the Black Swan isn't as highly regarded by Redditors now, if she's remembered at all.

Penguin (Sherri Shepherd)

Sherri Shepherd, The Penguin, poses on stage in The Masked Singer

There have been many bird contestants in The Masked Singer to date, from the Swan to the Black Swan to the Snow Owls and many more. One of the earliest birds was featured in season 2, the Penguin, who was eventually unmasked as television personality and former co-host of The View Sherri Shepherd.

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Even though Shepherd did make it pretty far into the competition, Penguin was still a contestant that never resonated very much with audiences. As Redditor Norfolkboy123 summarized, "I'd forgotten there was a penguin." So did many other Redditors.

Panda (Laila Ali)

Laila Ali, as Panda, sings in The Masked Singer

It's a common trend in recent reality TV for athletes to take part in lighthearted competition series. But a recurring theme of forgettable contestants on The Masked Singer seems to be athletes, no matter whether they were football players, basketball players, or even professional boxers.

One contestant mentioned frequently by Reddit users was Panda, revealed to be Laila Ali, the daughter of boxing legend Muhammad Ali. According to Redditor AlanKazam424, it wasn't just Ali's reveal that was forgettable. Everything about Panda was forgettable: "100% don't even remember what she sang or how it sounded or anything. Hardly remembered who it was."

Deer (Terry Bradshaw)

Terry Bradshaw, as Deer, poses on stage in The Masked Singer

One of The Masked Singer's earliest masked performers was also one of the series' most famous celebrities to date. The Deer, who competed in the series' 1st season, was unmasked as NFL legend Terry Bradshaw.

But no matter how famous Bradshaw may be, Deer is one of the most frequently suggested contestants within Reddit discussions of forgettable characters. Redditor DistanceIndividual noted that "I like him too, but I always have a hard time remembering him." Bradshaw may have been a strong performer, but the Deer didn't leave a lasting impression.

Pineapple (Tommy Chong)

Pineapple, Tommy Chong, sings on stage in The Masked Singer

Sometimes, there have definitely been generational divides within the audience of The Masked Singer. Season 1 contestant Pineapple might be one of the most obvious examples of this trend. Regarding the Pineapple, Redditor libertyy92 put it in an incredibly blunt manner: "Who are you again?"

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Anyone over a certain age would easily know the man behind the Pineapple mask, Tommy Chong, as half of the legendary comedy duo Cheech and Chong. But not even Chong's comedy icon status could have made Pineapple a long-lasting contestant. His visually unappealing costume and boring alter-ego didn't help matters.

Eagle (Dr. Drew Pinsky)

Dr. Drew as the Eagle with two men in black suits in The Masked Singer

Reality television figures are ones that have always been hit or miss with audiences. Even though they're watching a competition series, it was never a guarantee that viewers would take to the crossover from other reality series, or even remember them after they were eliminated.

In season 2, Eagle was revealed to be Dr. Drew Pinsky, a television doctor best known for the celebrity version of his reality series, Celebrity Rehab with Dr. Drew. As Redditor maggiehascats wrote, "I regularly forget about the eagle being on there so." Neither the Eagle costume nor Dr. Drew himself left a lasting legacy on the series.

Ice Cream (Ninja)

Tyler Blevins aka Ninja as Ice Cream beside Nick Cannon on The Masked Singer

There have been many famous celebrities to appear on The Masked Singer, but occasionally, there are contestants who leave viewers scratching their heads. Ice Cream appeared in season 2 and was quickly unmasked as professional gamer Tyler Blevins, better known as Ninja.

But Ninja was only familiar to those who were aware of the gaming world, which apparently has a very small overlap with The Masked Singer's audience. Redditor 3rdgradeteach86 put it as simply as they could: "Ice cream. Still don’t know who the hell Ninja is."

Hippo (Antonio Brown)

Hippo, Antonio Brown, and Nick Cannon on stage on The Masked Singer

It was inevitable that Hippo would be easily forgotten, given the fact that he was the first contestant ever eliminated on The Masked Singer. Hippo, unmasked as NFL player Antonio Brown, is perhaps the most frequently mentioned contestant in Reddit discussions.

As Redditor JimmiElaine wrote, "Guess I would have to agree with those saying Hippo because I absolutely do not remember there being hippo on the show. Who was inside?" Some Redditors note that Hippo was only memorable to them because of their NFL fanship and Brown's frequent appearances in news headlines.

NEXT: 10 Rules The Singers Must Follow On The Masked Singer