Jinx vs Karthus Counter Pick

Karthus in the bot lane is a niche choice, and 436 games on patch 16.13.1 is a thin record by bot-side standards. The figure it produces is still stark: 45.6% for Jinx, listed as Hard, and the mechanics behind it are consistent enough that more data would probably not rescue the matchup.

Attack range says Jinx should win, 525 against 450, but Lay Waste is a delayed blast placed anywhere within a radius rather than an attack, and it deals increased damage to isolated enemies, which is precisely what a carry standing behind her own wave becomes. Wall of Pain cuts movement speed and magic resistance for anyone crossing it, and Jinx at 325 movement speed with no dash is the worst possible target for that screen. Defile then drains health from everything nearby while she has no way to break contact, and it refunds him mana on every kill, so the pressure rarely stops for resource reasons. Death Defied keeps Karthus casting after he dies, meaning a trade of one kill for another does not end the threat, and Requiem reaches every enemy champion on the map regardless of position. Her counterplay is timing rather than statistics: Flame Chompers! stops the walk-in, Zap! reveals and slows before Defile is in range, and Super Mega Death Rocket! punishes a three-second channel cleanly. Scaling to 2,415 health means little against magic damage without resistances. The Karthus page lists his numbers.