Zhonya's Hourglass needs a rework
This item is interesting in nature. It gives squishy AP champions an opportunity to build defensively. It's especially useful against assassins. Unfortunately it also has the side effect of being too useful for assassins. EX: Fizz, Akali
Zhonyas, for the most part, is fine. The active has a long cooldown and it can be easily punished. The biggest issue I see is when it is combined with high damage assassins who have slippery kits by nature (namely the two I listed already - Fizz and Akali). Akali jumps on her target, shrouds, finishes her burst cycle, and then casts the Zhonya's active to negate the 4 CC and burst abilities that are flying at her from the victim's teammates. Fizz completely overextends into the enemy team, gets a kill with his burst, casts Zhonyas, and then his cooldowns are back and he slides right back out of the fight untouched.
Despite this, I think Hourglass is a good item. A necessary item, even. The main reason I would cite is because it gives mages the defenses they need against these very same assassins (amongst others). It's the only thing that keeps many immobile mages viable. So how do you rework the item so that mages will use it, but assassins will not? That's where it gets tricky.
One approach could be reducing the total AP on the item and increasing the resistances. Assassins by default want to rush high amounts of AP. If Zhonyas gave 60 or 80 instead of 120, Fizz might think twice about that Lich Bane -> Zhonyas build.
-So in that vein, I'd recommend adding a new intermediate item to the game that builds into Zhonyas in place of the needlessly large rod. A twin to seekers armguard that gives magic resist and stacks. The final Zhonyas item would be ~~60 ~~ 80 AP, 40 armor, and 30 MR with the invincibility active.
The above may not solve the issue. But ideally with only 60 AP, assassins like Akali and Fizz would not be able to afford this item in their build unless they wanted to surrender the majority of their burst damage. That's my suggestion, what do you think? Any other alternatives?
