There's actually a band with a similar image to Slipknot, called "Mushroomhead."
In 1997, the Cleveland band Mushroomhead was trying to finally sign with a record label. Roadrunner Records was one of the contenders. Mushroomhead sent them their promotional materials: photos, posters, videos, and albums. The label managers took a long time to respond. But in 1998, they asked the band for new material to make a final decision about the contract. At that time, Mushroomhead had just started recording their next album. As soon as the raw material was ready (the future album "M3"), they sent it to Roadrunner Rec. To their surprise, the label responded that they were no longer interested, as they had signed a contract with another band in masks (Slipknot).
The Cleveland musicians were even more surprised when they saw who had taken their contract. Slipknot wore the same jumpsuits. Bassist Paul Gray wore a pig mask, just like Mushroomhead bassist Jack Kilcoyne. DJ Sid wore a gas mask, just like Mushroomhead drummer Steve Felton. And Jim Root wore a BDSM mask from a sex shop, just like Mushroomhead dancer Marko Vukcevich.
Mushroomhead reacted to this situation in the most sensible way, deciding to radically change their image. The masquerade masks were replaced with uniform X-Face masks. And in retaliation, the album M3 included the song "Xeroxed."
Later, another song contained a hint about Slipknot. On the album XIII, you can find the line in the song "Our Own Way": "Despised imitators engaged in plagiarism, but dictatorial ambitions are false."
Initially, there wasn't a real conflict between the bands. It was all started by the fans. However, it should be noted that it wasn't without reason. Sean Crahan said in one interview that Mushroomhead was a terrible band. This served as a catalyst for the conflict. And the next time Slipknot came to Cleveland (Mushroomhead's hometown) for a concert, they received a "warm" welcome. One of the audience members threw a 9-volt battery onto the stage, which hit Paul Gray in the forehead. And the audience began to chant "Mushroomhead!" Corey Taylor, Mick Thompson, and one of the technicians came down from the stage and started a fight (for which Mick and the technician ended up in jail). In a subsequent interview, Corey commented on the situation, saying that it was all staged by Mushroomhead. Although Mushroomhead frontman Jason Popson personally wrote apology letters to each member of Slipknot, even though Mushroomhead didn't even know about the planned prank. However, the apologies were not accepted, and Corey threatened to beat up everyone in Mushroomhead. This is how a verbal exchange between the two bands began, which can be traced in the magazines of that time. Sean Crahan did not miss an opportunity to call Mushroomhead terrible, to which Mushroomhead producer Steve always responded with one phrase: "Come to Cleveland, and we'll sort it out." But Slipknot ignored these offers, probably because Steve promised to knock out all of Corey Taylor's teeth. Things started to improve in early 2002, when Corey sent a message to Steve (Mushroomhead's producer) on his answering machine, saying that he no longer held a grudge against them and wished them success. Since then, relations have improved somewhat. Mushroomhead and Slipknot stopped calling each other names in the press and exchanging threats. But a personal meeting was delayed. Mushroomhead met Slipknot in person only in early 2005 in a Cleveland bar. What they talked about is unknown, but after that, they started badmouthing each other again.
:)