A large section of the patch 9.6 notes talks about “ability proc consistency,” but what does that mean? It means that Riot Games changed how some spells are classified, so they interact with on-hit items and runes differently now.
On-hit effects are all unified now
If a skill would trigger an on-hit effect for a rune, it will now also do it for items and vice versa. (This wasn’t the case before.)
For example, if an ability activates Arcane Comet, it should also activate Rylai’s Crystal Scepter.
Damage over time abilities that’re also area of effect are now marked that way
Before they were labeled as one or the other, but now they’re labeled as both. This includes abilities like Anivia’s Glacial Storm, Fiddlesticks’ Crowstorm, Katarina’s Death Lotus, and more.
Abilities that are both DoT and AoE that trigger on-hit effects will take the weaker effect, too. This means if an Anivia ults with Arcane Comet, the comet will do five percent damage since it’s a DoT, instead of the higher 10 percent for AoE.
Pets trigger on-hit effects when they attack
Pets like Elise’s Spiderlings or Annie’s Tibbers will now proc the same effects. Malzahar’s Voidlings triggered on-hit effects like Rylai’s before, so now Riot has made sure all pets do across the board.
What all this does is just unify skills. There were a lot of questions before about why Glacial Storm triggered a specific item or rune when Jayce’s Lightning Field didn’t. This means more skills will activate runes and items effects, so it’s time to buy some more on-hit items.