We need to talk about Venomancer.

He is not fun to play against, that's it. It's beyond Techies level of no fun allowed, because at the very least you can blame techies on yourself "Oh man I should buy some sentries next time", nothing like that, we can spam as many wards as he wants to because they have outrageous low cooldown and low mana cost, allowing him to dominate any lane in a way no hero can do, making the very act of farming a nightmare. You get punished by trying to break them because they have more range than 99% of heroes and can use Venomous Gale, which is his main source of damage aside his ultimate, plus the fact that venomous gale initial damage stacks, this mean you can be bursted down by 5 or more venomous gales at the same time without even being close to Venomancer.

This is should be already be enough to convince you he is no a health match up, but if you don't think it's enough just wait there's more.

Octarine Core magic life steal works with all his skills, that plus the fact he can effectively poison your entire team, which is not a rare occurrence because his aghs makes his ultimate spreads as long as you are close to someone, he can heal TONS of health per tick, and I mean really big chunks of health. So as you try to kill him, you health dropping harder than Barathum charging on Bloodseeker's ultimate, he heal even faster because he also poisoned your teammates, but you are also fed and he is dropping low, then Guardian Greaves activates making him even tankier and his regen even stronger. giving him just enough secs to kill you while he almost full HP again... but then! Your teammates shows himself and goes for his troat... but he has also Blademail and laughs at your teammate trying not to right click him while his poison, while also healing him.

EVEN IF AT THIS POINT you don't think this piece of shit is pure cancer, I've got my personal favorite yet, his fucking disables. By "disables" I mean his slows, and got so many slows, and they seem to last just forever, slows that are impossible to evade because he can pop a ward just beside you at any given moment and can't be dispelled by any means, that includes BKB. It's SO FUCKING annoying. That is just the cakes cover, there's still the fact that IMBA Skadi works with ANY damage, that include poison, which means EVERY VENOMANCER SKILL can slow you the fuck down and make me wanna punch my screen.

Skadi, Blademail and Octarine Core are just enough to FUCK YOU UP (I didn't include aghs because he can consume it now), he doesn't any damage itens, he just need to stay there and not die while his poison do the work, it does scale with spell power but he can still deal shit tons of damage without it, a rapier is welcome later. There's also the new spell power item that activates with any magic damage, even the minor wards attack, and it resets on every poison tick and it also works with skadi, it was such a huge boost on a already annoying hero without any second though given to it, it just make me even more mad.

TL;DR: He may be killable, but that's extremely hard, but can be won, but he is going to suck the pleasure from playing dry.