I'm assuming this is the sort of nerf people want to see.
Innate -- Contempt for the Weak: Zed's basic attacks against targets below 50% health deal 6%-10% of the target's maximum health as bonus physical damage. This effect can only occur once every 10 seconds against the same target.
Q -- Razor Shuriken: Zed throws his spinning blades forward, dealing 75/115/155/195/235 (+100% Bonus AD) physical damage to the first enemy and 60% damage to enemies thereafter.
Range: 900 800
Cooldown: 6
Energy Cost: 75/70/65/60/55 75 Energy
W -- Living Shadow:
Passive: Zed gains 4%/8%/12%/16%/20% Bonus Attack Damage.
First Cast: Zed's shadow dashes forward, Zed projects his shadow forward, remaining in place for 4 seconds. His shadows mimic his basic abilities at 50% effectiveness. If Zed strikes the same target with both portions of a basic ability, he restores 20/25/30/35/40 Energy.
Second Cast: Zed blinks to his shadow's location, swapping places with it. Zed must be within a certain range to use this ability.
Range: 700
Missile Speed: 1750
Cost: 40/35/30/25/20 Energy
Cooldown: 22/20/18/16/14
E -- Shadow Slash: Zed spins his blades, dealing 60/90/120/150/180 (+80% 75% bonus AD) physical damage to enemies around him and reducing Living Shadow's cooldown by 2 seconds for every champion hit.
Range: 290
Cost: 50 Energy
Cooldown: 4
R -- Death Mark: Zed becomes untargetable for 0.75 0.5 seconds and dashes behind the target enemy champion. Upon arrival, he ghosts for 3 seconds and applies a Death Mark to them, spawning a shadow at the cast location that lasts for 6 4 seconds. After 0.5 1 second, Death Mark can be reactivated.
The Death Mark debuff stores 25%/35%/45% of all physical and magic damage Zed deals to the target while marked. After 3 seconds, the Death Mark detonates, dealing the stored damage to the target +100% of Zed's Bonus Attack Damage.
Second Cast: Zed swaps places with his Death Mark shadow. This consumes all other shadows.
This is the kind of nerf we want. Entries in strikethrough are removed from the original. Entries in bold are new. An entry with a strikethrough next to a bold is where the strikethrough was changed to the bold.
This is the kind of nerf that hits him where he needs hit. A summary:
Contempt for the Weak now deals physical damage instead of magic damage. This makes the effect of itemizing Armor against Zed stronger.
Contempt for the Weak on-target cooldown is now a full cooldown. This will reduce Zed's ability to farm under tower, making pushing him into his tower an effective way of keeping his farm low.
Reduced the range on Razor Shuriken.
Razor Shuriken now keeps its full Energy cost at higher ranks.
These changes should reduce Zed's ability to poke and farm with Razor Shuriken, forcing him into melee with the minions more often so he can be poked down.
Living Shadow is now a projectile. This allows projectile mitigation to destroy (in Yasuo's case) or block (in Braum's case) Zed's shadow, affecting his ability to get into fights and allowing Yasuo and Braum to be counter picks to Zed.
Reworked how abilities interact with Living Shadow (not really a nerf or a buff).
Shadow Slash no longer reduces the cooldown of Living Shadow. This should make Zed easier to lock down and less mobile.
The AD ratio of Shadow Slash was reduced by 5% of bonus AD. This will reduce his ability to deal high damage to more than one target at a time.
Death Mark's untargetable duration is reduced from 0.75 seconds to 1 second.
Zed has to wait longer after using Death Mark to swap back to the Death Mark shadow (1 second, up from 0.5).
Zed has 4 seconds to swap back to Death Mark shadow, down from 6.
These changes are to make Zed more able to be locked down, hitting his safety.
Death Mark only amplifies physical damage Zed deals and no longer affects any magic damage he deals. (This is only as a result of the change to Contempt for the Weak)
Swapping back to Death Mark's shadow consumes any active shadows on the battlefield. This will reduce Zed's impact on a teamfight after he has used Death Mark.