Talk:Infinity Edge/@comment-24090662-20140914111405/@comment-10428734-20141126204130

Some fun calculations about critical strike (with no crit runes):

The critical strike chance and passive from IE alone grants +32.5% DPS.

IE+Triforce grants +52.5% DPS. IE+Ghostblade grants +60% DPS. IE+Statikk grants +67.5% DPS. IE+PD grants +82.5% DPS.

As comparison, Rabadon only grants +30% AP (+36.5% with Archmage). Furthermore, this bonus does not affect base damage, so the actual damage dealt is only increased by ~20-25% depending on how much AP you already had.

As another comparison, PA's crit (the biggest crit in DotA, which is so strong it is her ultimate ability) grants "only" +52.5% DPS at level 16+ (this multiplier being exceeded by IE plus any other crit item).

Let's now calculate the value of IE in a full ADC build:

Considering a level 18 Ashe (I took Ashe to make maths easier, since she has no steroid or on-hit effect, IE would be even more effective on other champions) having standard ADC runes and masteries and a standard Boots+BT+PD+LW+IE+Defense build.

Without IE, that Ashe would have 100 + (8 + 16 + 80 + 40) x 1.05 = 251 AD

With PD providing +30% DPS, this gives us 251 x 1.3 = 326 Damage Per Attack (AS does not matter since IE does not affect AS)

With IE now, that Ashe has 100 + (8 + 16 + 80 + 40 + 80) x 1.05 = 335 AD

With IE+PD providing +82.5% DPS, we now have a total of 335 x 1.825 = 611 Damage Per Attack

Therefore, buying IE effectively increases Ashe's average damage per attack by 285 (611 - 326), or 87.42% (285 / 326).

If we just assimilate those 285 bonus damage per attack to 285 AD, we obtain a statistical value of 10260g (285 x 36), which gives us a 270% gold-efficiency (10260 / 3800).

More precisely, if we calculate the amount of AD you would need to buy instead of an IE to reach the same DPS, we obtain 219 AD (285 / 1.3), for a statistical value of 7884g and a gold-efficiency of 207%.

This already makes IE the one of the 4 finished items that can exceed 200% efficiency (with SotO, Mejai and Locket IF you count the active as bonus health).

As a comparison, a Rabadon gives roughly 280 AP with a full AP build (not considering champions like Cassio or Veigar), which is worth 6090g (280 x 21.75), for a gold-efficiency of 184% (6090 / 3300). (But we all know that AD scales a lot harder than AP, so gold spent into AD is even more effective)