NA used chamber the best out of every region. Everything last year was based around chamber, even Franchising in NA was built around still having a "chamber" rather than a duelist. It's hard to expect teams and players to readapt after a full year of using a specific character. We talk about how Yay is a "Chamber Abuser" when it's literally the same with Derke on Jett. Derke is a more aggressive player and Op-er than Yay is, thus he's built way better for playing a Jett role. Is Derke a Jett abuser though? No, the agent just compliments how he plays. Is Mako an Omen abuser? No, the agent just compliments how he plays. Chamber compliments how guys like Cryo and Yay would play. Look at Leaf. Leaf on Chamber isn't half of what he is on Jett, because he excels with those aggressive plays.
TL;DR. Chamber compliments Yay and Cryo just like Jett compliments Derke, Aspas, or Leaf. It's a matter of perspective, it's a matter of playstyle, it's a matter of meta. Comparing a game that nerfs whatever is good after a year to itself is like comparing Minecraft to Terraria.
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