This ain't late season 2... Jayce doesn't work well for a lot of comps, especially comps that lack big tanks or other bruisers. He's supposed to poke and poke your brains out until the enemies can be bursted down, and outside of poke he's all utility.
Jayce is a great champ, but after season 2, he lost a good amount of his burst, and his poke is less spammable remedied by tear, which ends up reducing your early game potential.
He has a below average win rate, but that's usually for people who try to spam him every game. My recommendation is that Jayce is a champ you just know how to use, especially in a poke heavy team with Ez or Lux. He's an extremely fun champ though and is my current favorite character
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