Would it be too gruesome? Do you think it would be good for the game? I think Blood Zac would be a cool skin. Crimson or Red Zac might look a little terrifying therefore it would be fitting to release it on a Harrowing event.
The issue with skins is that Riot only wants to make a skin if it offers significant model differences compared to the base model. Had Zac been one of Riot's first champions, we probably would've seen such a skin, as the early skins effectively amounted to just recoloring the model. They've shied away from this practice though, as they want to give us more bang for our buck.
The fact that Riot has released a Chroma Pack for Zac that didn't include a red version might lead one to believe they have such an idea in store for him later down the line. Heres hoping.
