In-game (and on league of legends site for lux's information) once the spell gets to rank 5 (light binding) it says that the second half of it (if it hits 2 targets) does 3% of the effect. This needs fixing. If you don't believe, go test .-. Or just look it up on the site, it says 50/50/50/50/3%

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On the sight.

Have you actually tested the ability, or are we talking about tooltips?

lux's late game was too powerful, so they toned down her Q at max rank

nobody cares about lux

laughed so hard.

so THIS is why she falls off late game