DotaStrategy.com - View topic - The Butterfly/The Assault Cuirass.

WhyIsLife

First Blood Posts: 12 Joined: 05 Sep 2007 486 gold

The Butterfly/The Assault Cuirass.

Posted: Wed Aug 27, 2008 12:28 pm

My ultimate point is this:
Many people buy the assault cuirass when the butterfly would be more appropriate.

I will state the cases where I concede the the Assault Currass is a better item and when I think the butterfly is a better item.

For referance:

Butterfly:
6000 Gold

30 Damage** (60 damage on an agility)
60 Attack Speed
30 Evasion
4.1 Armor (30/0.14)

Assault Cuirass:
6120

0 Damage
55 Attack Speed
15 Armor
-5 Armor aura

I have done my homework here:

Let's treat the attack speed as equal.
Let's treat the price as equal.
I'm going to treat the butterfly as an item on a NON-agility hero.

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SURVIVABILITY

In terms of EHP enhancement, butterfly offers 4.1 armor and 30% evasion vs the 15 armor of the Assault Currass.

For a hero with 0 armor:

The AC offers 47% damage reduction.
The Butterfly offers 43.65% damage reduction.*

*[(4 armor) - 19.5% damage reduction + 30% evasion. Therefore the butterfly offers (30+(19.5%of70)% damage reduction = 43.65% damage reduction]

For a hero with 10 armor already (37% damage reduction):

The AC offers 60% total damage reduction.
The Butterfly offers 61.65 damage reduction

*[(14 armor) - 45% damage reduction + 30% evasion.
Therefore the butterfly offers (30+(45%of70)% damage reduction = 61.65 damage reduction.

MY POINT: At 10 armor or any higher, the Butterfly offers a higher survivability. And it obviously going to be late game when people can buy a 6k item. As the game goes further and further on, the butterfly will become more and more effective than the AC as a survivability item.

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DAMAGE INCREASE

Let's assume (like above) that during this period of the game, a hero will have 10 armor (0.375 damage reduction).

Now, the 5 armor reduction reduces their armor to 5, or 23% damage reduction, thereby increasing the potency what your attack would otherwise be by 123%.**

**[The calculation of (100-23)/(100-37.5)]

So, lets assume your hero deals 120 damage (outside the butterfly/AC) and he is fighting against a hero with 10 armor.

With AC he would deal ((100-23)% of 120 damage)
= 92.4 damage.
With Butterfly he would deal ((100-37.5)% of 120+30 damage)
= 100 damage.

Now I am sure you are thinking, 'later on in the game, people have higher damage per attack and the amplification of AC rather than point increase in damage of Butterfly becomes more valuable'. - However, I would like to point out that the armor reduction becomes simply less effective as armor gets higher (20 armor - 5 armor is a lot less crippling that 10 armor - 5 armor).

So I will simulate the same with 20 armor on the victim hero and 200 damage (or 230 damage with the butterfly).

With AC he would deal ((100-47)% of 200 damage)
= 106 damage
With Butterfly he would deal ((100-54)% of 230 damage)
= 105 damage

I will concede now that at this point, and any later in the game, the AC becomes a better DamagePerAttack item on any non-agility hero.

(On an agility hero the Butterfly almost always remains a better DamagePerAttack item - [outside cases of a DK with Shiva's, A plate mail and his own AC] - but that's off the point).

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CASES OF USE ON BOTH ITEMS:

Now I will highlight the occasions when someone should use either item.

Butterfly is appropriate when:
- You have an agility hero
(With the exception of Darkterror and Mortred who have a natural evasion).
- Your hero has armor higher than 11/12.
- You have low natural damage.

AC is appropriate when:
- Your hero has has an armor reducing spell.
(Such as Slardar's amplify damage, Tidehunter's Gush) or is carrying the Stygian Desolator.
- Your hero has less than 7/8 armor.
- Your hero has summons (Furion or Visage).

ONE LAST NOTE:
Construction of the assault cuirass is easier as it comes in 4 pieces of 620, 1400, 2000, 2100 than the butterfly which is 900, 1800 and 3300.
One must note on the other hand that the assault currass leaves with only 3 slots during the building (and I'm a huge fan of filling all the slots with all sorts of items0.

More heroes fall into the butterfly category.
(EG I was scolded the other day for buying butterfly rather than assault cuirass on Pit Lord, when - due to reasons above - it was way more appropriate).

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Finally, please appreciate how much effort I have put into writing this and it's really annoying for everyone when some writes an one liner with AnNoYiNg AlTeRanT\aTe TpyinG nad BAd SepllInG.

lol, thanks for reading.