Treehugger!

Impetus (T)
Gives strength to the Enchantress' attacks, causing them to deal greater damage the further away the target is. Damage type is pure.
Level 1 - Deals 15% of the distance in damage, with a 375 damage cap.
Level 2 - Deals 20% of the distance in damage, with a 500 damage cap.
Level 3 - Deals 25% of the distance in damage, with a 625 damage cap.
• The maximum damage is dealt at 2500 range. If this distance is exceeded, no bonus damage will be dealt.
• You can target magic immune units with this skill, but the bonus damage will not be applied.
• Distance to target is measured when projectile hits, meaning that running away from the target after using Impetus will increase the damage dealt.
Mana Cost: 55/60/65
Cooldown: 0
Comment: Your heavy damaging orb ability that deals PURE damage (go purity!) and pierces magic immunity. This gives you potent attack power in many situations (of course depending on how far the target is) such as harassing, chases, and clashes. You can wipe out softies with impetus.

Item Build:

1.
Bracer (510)
6 Strength
3 Agility
3 Intelligence
Gauntlets of Ogre Strength + Circlet of Nobility + Bracer Recipe Scroll
Hp and Str boost. Can be replaced with Nulls. Disregard it if you wish, if you lane against a soft hero, or if you aren't up against a good harasser.
2.
Null Talisman (485)
6 Intelligence
3 Strength
3 Agility
Mantle of Intelligence + Circlet of Nobility + Null Talisman Recipe Scroll
Replace with Bracer if you wish. If you have no problems with mana, disregard.
3.
Boots of Speed (500)
50 Movement Speed
Note: Movement speed bonus doesn't stack with Boots of Travel, Phase Boots, Power Treads, or Boots of Speed.
Speed. Plain and simple.

Early Game:

So you just picked Aiushtha! Yay! Without even an attention grabbing introduction with silly metaphors, we skip immediately to evaluating Aiushtha's Pros and Cons:

Pros:

-Great supporting abilities
-Great pure (unreducable) damage and magic immune piercing orb ability (leading to next point)
-Shines in mid game
-Can be a team player
-Respects the environment like David Suzuki! (if you don't like him, screw you!)

Cons:

-Horrible Str gain (+1 only!) and leading to my next point...
-Susceptible to nukes
-Low starting mana pool
-Doesn't shine as bright in late game (but impetus still hurts!)
-Just a bit less than average MS

As mentioned above, poor Aiushtha is FRAGILE but powerful at the same time. Impetus is her main attack power source (PURE damage and pierces through magic immunity!) and it's an orb. So if you manually cast this upon your enemies, it won't trigger creep agression, meaning Aiushtha can harass without getting getting torn to shreds. Harass as soon as you get impetus, but harass responsibly (yes, I know that doesn't sound right).

Skill build:

(Replace untouchable with enchant if you wish)

1.NA
2.U
3.U
4.NA
5.U
6.I
7.NA
8.NA
9.U
10.E
11.I
12.E
13.E
14.E
15.St
16.I
17-25.St

Here we start off with Untouchable, that way, we slow our enemies' attack speed when they attack us and we can save our tiny hindquarters from mean harassers. This means that we may have a bit of trouble supporting Nature's Attendents and even impetus later on but a few clairities can take care of that (and possibly your other items). You will notice this is more of a skill-based build, we don't buff our stats until level 15-ish. This being said, enchant is learned earlier than the other build so we can slow people down and pummel them with Impetus.

But it's not like we have to get Untouchable first; sometimes getting a kill (or First Blood) is more important to you, especially if you're facing some heroes that stay back and barely (or don't even) harass. Then getting enchant might be better. Keep in mind what type of spells the opposing hero has, "mia" calls (or missing in action meaning an enemy hero has disappeared from another lane) and also the opponent's behaviour.

Anyways, we try to max-out either untouchable or enchant; while maxing out Nature's Attendants in the meantime, making it so you're more potent against enemies in Mid game (where you go and gank and possibly push), and you're also safe thanks to Nature's Attendants. However, it can't keep you alive from multiple heroes chasing you down, so be careful when you're chasing and notice your enemies' allies' movements (sudden "mias" for example).

Late game wise, you become more of a support hero. You know, healing allies, slowing down other heroes and disabling them with your items. Impetus still hurts and is still important, just not as much as Mid game because people buy insane items at this stage, and carries, DPSers, and even tankers bring out their full potential. This makes it harder for Impetus to kill.

We evaluate the items now:

-Bracers (1 or 2 or replace with Nulls for mana + damage) for the HP we need. Ignore if you don't need them and skip to boots and core item.
-Boots of Speed for, well, speed (surprise eh?).
-Str or Int Treads for more damage or HP, but don't get it if you want Boots of Travel for more speed (your skill Enchant can't save you from 3+ heroes chasing you).

-Now we get to our core items. We have a variety:

for the damage, mana regen, some intelligence, the soul burn, and attack speed. Amplified damage from Soul Burn goes perfectly with impetus.

for basic survivability and mana. Good to beef Aiushtha up if you keep dying.

for the disable, intelligence ,and mana regen. Great to use against chasers

Pick the one you need the most. Orchid (costs 5025 gold) and Bloodstone (5050 gold) is cheaper so getting one of those is better if you're having trouble farming and last hitting. Guinsoo, however, is more expensive (5675 gold) but the hex is very effective in saving your (possibly allies') butt(s), 1 vs. 1, and in chasing.

- Moving on, we have a choice of secondary items which gives you more flexible choices:

same as above but don't get this twice!

that extra MS and teleport helps greatly.

boosts enchantress' endurance, intelligence, and gives a good aoe slow.

same as above, don't get twice, you know the drill.

Secondary item choices depends on the situation and are more flexible than core item choices, meaning a Black King Bar or Kelen's Dagger isn't a bad idea.

After the secondary item is made, you can pretty much get what you want or need.

To sum it up, I have made a chart of the choices of items you should buy:

Now that you understand why I chose these these builds, we move on to the early game role and info.

Role: Simple; farm and deny (and possibly harass a little though concentrate on the denying and last hitting).

For more info on denying and farming and other such issues, visit Ghost's guide to DotA:

www.dotastrategy.com/forum/ftopic10674.html under denying and farming (so friggin' obvious...)

Moving on, we either go bottom lane for sentinels (top for scourge) or the mid lane (for both). Being in bottom lane (sents) or top lane (scourge) means your creeps battle your enemies near your tower, so you're pretty safe (and you have low HP, perfect match). Mid lane however, provides flexibility for ganking (as you can go top or bot) and better rune control. It's really up to you, but do know that early on, you're not a hero killer. You don't have impetus just yet and you're fragile (can't expect much from an elf that wears a bra made of leaves and grass). Concentrate mainly on denying and farming.

Our starting items should be:

Bracers and Nulls included:

The circlets will prepare you for getting bracers/nulls and the clarities boosts your mana for heal/slow.

Without the circlets if you don't want bracers or nulls:

The ring of basilius will grant enhanced mana regen, a bit of damage, and some good old armor. Perfect for Aiushtha and her low hp. The clarities, like above, is used to support her spells.

As the game progresses, we get our Bracers or Nulls (if you chose not to get Bracers, skip straight to the boots) and Boots of Speed. From here, you choose: Treads or save up for your core item and boots of travel later? It depends on your need for Str or Int versus your core and movespeed. As a mid game int, I usually go for Travel for the speed and getting my core earlier but it's totally your choice. Treads can be good too, it provides int thus giving you damage and mana. For Str treads, it gives her an HP boost. So you be the judge, though I will advise 'the boots of travel and core' path because of your need for speed to escape dangerous situations and your core is important in Mid game.

Feel free to use Nature's Attendents to heal your lane partner or you but keep in mind, you have a small starting mana pool. Wait for it to grow later and you can use it more often and increase it's level for greater effect.

By the end of early game (around lvl 6 when you get impetus), you should have this:

Any core (Treads):

Orchid Core (Travel):

Guinsoo/Bloodstone Core (Travel):

As you can see, the decision of Treads and Travel really changes what items you get. If you don't have the Bracers, you should buy parts of your core with the spare 1020 gold.