[Gameplay] Fiora's riposte doesn't work against certain champion abilities.
Trying to parry abilities with a secondary effect where the first one "marks" you or applies a unique debuff has no effect. For example parrying the first part of Zed's ultimate, as well as Urgot's still allows their mark to be applied and you to still take the damage/get executed respectively. Reproducible 100% of the time. Other examples include Akali's E, Diana's Q mark, and the mark from LeBlanc's Sigil of Malice. Try parrying any of these abilities or similar ones and you'll see what I mean.