The greatest picks out of lane to counter Jarvan IV include Jinx, Caitlyn, and Aphelios. These champs are all good at countering Jarvan IV with decent win rates over 55%. Even if these Jarvan IV counter picks are not chosen in your lane, it's not a good idea to play him into one of these matchups. They will very likely destroy Jarvan IV.
Conversely, if the enemy team brings either Karthus or Ziggs, you should seriously consider taking him, as he easily crushes these champs with win rates over 54% against each ofthem.
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