I'll be going through a comparison of some of the items you can build on Zed and discussing strengths vs. weaknesses.
This is the #1 Item in the game for Zed. Fully farmed, this item gives a flat 100 AD plus 8% lifesteal. With Zed's W passive, the AD on this item is bumped up to 125. And Zed has a 100% AD scaling rate with both Razor Shuriken and Death Mark, and a 90% AD scaling rate with Shadow Slash. With 2 of these fully farmed, that means all of your abilities are doing more than an additional 225 damage on the target. It also means your AA, when you hit them with it, is hitting like a freight train.
On the surface, it seems like a good choice on Zed. It adds 87.5 AD, a chance to crit, and increased crit damage. Some would be tempted to rush this item. Don't do this. This item is based on the need to AA. Zed only needs to AA at one point in a fight... when the enemy's hp is less than 50%. The rest of the time Zed is just bursting someone down, dealing as much damage with his abilities as possible. This item is only worthwhile as a late-late-late-game item, and only if you have another item with crit on it, such as Trinity Force
Another seemingly good item on Zed. It has the second highest flat AD in the game, has increased lifesteal and health regen, causes attacks to deal damage in a circle around the target, and has an on-use effect that deals damage and drains life. In fact, this item is not bad to have on Zed. It adds 93.75 AD at end-game. But it should only be taken if the enemy has several bruisers who like to clump, and who don't have hard CC. This item is mainly used in conjunction with AA, but it's on-use effect does add to Death Mark's cumulative damage.
This is the next largest flat AD item (variable is included in this statement, as with 87% hp or less it overtakes the next largest AD item), adding 68.75 AD with passive W. It adds an additional maximum of 49 AD as you lose health (this is with 98% hp gone, an unrealistic combat point, but worth mentioning nonetheless) In addition, it adds flat Magic Resist and gives you a 400 MAGIC DAMAGE bubble should you take magic damage that would leave you at less than 30% hp. This item is very strong on Zed, making him very dangerous to casters, and granting him survivability in a slug-out with a fed APC. This should be your second completed item against teams running 2 or more AP based champions.
This is a very strong item for Zed, but very costly. With the increased cost of the Quicksilver Sash, the only time you should build this item is when the enemy team has a plethora of CC or a suppress. This grants 75 flat AD along with the 45 Magic Resist.
With 62.5 AD added, this item comes in next in the flat AD race. However, where this item shines is the added HP and especially the Armor Penetration. It boasts a flat Armor Pen of 10, and has a stacking armor shred of 6.25% x 4 (equalling 25% armor reduction). This effect stacks on the enemy champion, meaning if there are other players on your team attacking your target they also benefit from this debuff. What this really means though is that the target has 10 less effective armor right off the bat, and loses an additional 25% of his armor through repeated attacks. This effect is applied through any physical damage, and since everything Zed does is physical damage, he can apply this with any of his abilities as well as his AA. This armor shredding ability of the Black Cleaver is especially useful against high-armor champions / teams. The more armor they have, the more they lose through this item's effect.
This item gets an honorable mention, as it has a flat AD of 62.5 with Zed's W. It also grants passive hp regeneration and adds a red-buff type burn-over-time effect to any ability that deals physical damage. This applies to all of Zed's abilities, meaning that Zed can apply a 66 True Damage burn to every target he hits with any of his abilities. This item is not a horrible item to have on Zed, but it is not as good as others. If you have the money to buy this, you should be building another Bloodthirster instead. The only exception to this is if you are jungling, in which case this is the optimum item to upgrade your
This item has the potential to grant the most cumulative AD of any item in the game. At full stacks, it has a base AD of 110, giving Zed a total of 137.5 AD when fully stacked. In addition, you gain a movespeed bonus at max stacks, which is always helpful. This item is a very high risk / high reward item, as any death instantly drops 1/3 of the stacks from this item and instantly makes you much weaker. On the other side, if you snowball early and continue to rack up kills throughout the game, this item can let you wreck just about any enemy. However, another downside and hidden effect of this item is a global taunt, and I say that without humor. The enemy team, upon seeing this item in your inventory, will do their best to kill you every fight, no matter what. They will focus you above and beyond any other player on your team. Again, very high risk item. I personally do not suggest it unless you have a very strong mass CC type team.
50 flat AD makes this a decent item to have on Zed. In addition, it causes all of his autoattacks to deal 4% of the enemy's REMAINING hp in PHYSICAL damage, and grants half of that damage to Zed as hp. It also comes with a flat 10% lifesteal and an active ability that drains the target's HP of 150 x 50% of Zed's AD, healing Zed for the same amount and slowing the enemy by 30%. This is the
of the AD world, and on Zed this item can really shine. The active effect is added to the damage from Death Mark.
This item gives Zed 50 AD and 35% automatic armor reduction on whatever person he hits. This item's high % of armor penetration makes it incredibly useful against enemies high in armor. However, against opponents that aren't stacking armor, this item loses a lot of it's lustre. If the enemy team is building high into HP and ignoring armor, go for a bigger AD item or an item that has a flat armor penetration stat.
At 37.5 AD, this item is hardly a heavy hitter. However, it is still a strong item on Zed due to the fact that it packs a slow, movespeed increase, crit chance, attack speed, increased health, and a 150% BASE AD increase to Zed's next AA after using an ability. At 18, Zed has 109.8 Base AD, meaning this item's proc will make his next basic attack hit for an additional 164.7 Damage. This works well with Zed's ultimate and his champion passive. It can cause his AA to crit for well over 1100 when properly built up. However, it is an expensive item, and does have 2 stat increases that Zed doesn't need.
This item grants 31.25 AD to Zed as well as a 15% chance to crit and a passive debuff to the enemy he is AAing that reduces all healing effects on them by 50%. This item COULD be useful if the enemy team has a dedicated healer, or a large amount of lifesteal / spell vamp. Otherwise, the item slot is better used for something with a lot more AD, as ignite is a better heal prevention method.
25 AD is the end result of this item, along with a 10% move speed increase, 50% attack speed increase, 10% CDR, and 35% tenacity. Zephyr shines when the enemy team has lots of bruisers with lots of health and soft CC. It lets Zed transition from nuke burst to High AD, attack speed brawler. It also helps in chase or evade scenarios, with its increase to movement speed and reduction of all CC effects. This item should only be taken against teams with several AD based brawlers, and only when the boot choice was
37.5 Flat AD along with 700 hp and a great slow on basic attack. This item is a good alternative to a Warmogs if your team is already very tanky. It grants more AD than the Warmogs, and the slow on hit is good for sustaining damage on targets that attempt to flee. However, with the increase in escape mechanics on many champions, the slow isn't always a guarantee for continued damage on a target, and this item doesn't grant passive hp regeneration. The mobility of the enemy team needs to be taken into account when purchasing this item.
+45 armor and 15% crit chance are the non-variables on this item. Why is it included? A good Zed knows that HP is necessary for the late-game, when bruisers get very tanky and very capable of killing just about anybody. Zed has a base HP of 1975 at level 18 (Runes and Masteries excluded). With Warmogs, that's 2975 HP. At 1.5% of HP converted into AD, Atma's gives Zed 55.78 additional AD. This is a decent amount of AD for the cost of the item, and the extra armor is useful against heavy bruiser teams. This item should only be acquired when you build either a Warmogs or a Frozen Mallet + Black Cleaver.
At 1550 gold, this item grants 56.25 AD. This is the best unfinished item in the game to rush, and I would suggest getting this first every game.
This item grants 31.25 AD. If you can't afford a BF Sword, this is a suitable alternative to an early item.
At 31.5 AD, 10 Armor Pen, and 10% CDR, this item is very good for Zed's early game. However, at 1337 gold to buy, it should only be purchased if the money isn't present for a BF sword or after completion of the first Bloodthirster.
25 AD, 200 hp, chance to slow enemy. Only buy if being harassed hard early game, or if planning on building a Frozen Mallet or Trinity force after second Bloodthirster.
12.5 AD and 10% lifesteal. A good early-game item, but should only be bought after a BF sword.
12.5 AD. Only buy this item with extra cash and only if the plan is to buy a Vampiric Scepter, Brutalizer, or Phage.
12.5 AD, 80 HP, 5hp regen on basic attack. This item is decent to buy early game IF you have extra cash and feel the need for the extra early HP. It does not upgrade, meaning you effectively lose 285g if you sell it to buy another item.
This concludes the list of effective AD items for Zed.