The Harbinger Comes... Outworld Destroyer

Intro to Outworld Destroyer

Outworld Destroyer is the only Intelligence hero in Dota who qualifies as a hard carry. Much like any other hard carry, he requires a very high amount of farm in order to be truly effective, but unlike other carries, he's not necessarily reliant on a fast attack speed, but instead, careful placement on where he is when he fights against another hero, and building up enough intelligence so his auto-cast ability, Arcane Orb hits like a tank, and take down even the strongest of heroes with a few hits.

Here are a few pros and cons you should know about OD:

Pros

Excellent in the mid lane
Great harassment with Astral Imprisonment, which makes the laning phase a living hell for early casters
Next to no issues with mana management thanks to Essence Aura
Can be a Strength hero's worst nightmare
Sanity's Eclipse can potentially obliterate an entire enemy team mid-late game
Possibly the only counter to Anti-Mage

Extremely squishy, and building up strength or armour isn't a viable option
Like most int heroes, Magic Immunity shuts him down hard
Almost completely reliant on Arcane Orb
Astral Imprisonment must be used wisely, either to secure your kill or help you survive
Ultimate has a very long cooldown
Requires a tonne of farm
Pugna's Nether Ward can completely destroy you or render you useless in teamfights.

Items

The name of the game with Outworld Destroyer is stacking your Int stats as fast as you can. The power of your Arcane Orb is reliant on how big your mana pool is, and the effectiveness of Sanity's Eclipse is dependant on how much higher your Int is than your enemy, hence why strength heroes may cower in fear the moment they see OD float in.

Assuming you're going mid, his starting items are pretty standard; Tangos, and a Salve for survivability, 3x Iron Branch and a Mantle of Intelligence for some early stats. It's not a bad idea to build your mantle to a Null Talisman to beef up your last hitting power, but if your enemies are gank happy, it may be worth putting it aside for Boots of Speed.

Some people like to get a Bottle on OD when playing mid, but personally, I don't think it's necessary, and a waste of gold that could be going towards your int items (namely your Force Staff). OD has next to no mana problems, so the bottle would just be for HP to offset harass, and if that's a problem don't be afraid to get more Tangos, or a salve if you're desperate. Other than that, you can use Bottle for runes, but apart from haste, most runes are useless on OD, and of course, he's not a ganker. If you're doing well, and have decent communication with your team mates, you can probably secure some ganks in the side lane when you get your ultimate, but you'll probably need a good stun or slow to secure it, and your target should be a squishy one.

Once you've managed to build your Power treads, build up your Force Staff ASAP, not only does it give you some decent early Int and semi-decent HP regen, it gives you some escape and chase capability, and OD is in dire need of the former. Once you've got this, farm your way to a Scythe of Vyse, arguably the best Int item in the game and on OD this is no exception, especially since it also has an amazing disable with Hex. Fine a lone enemy trying to build up some farm, Hex them, then obliterate them with your Arcane Orb as they try to run away.

The earlier you get your Scyth of Vyse, the better, because it means you go from being a squishy farmer to a force to be reckoned with, especially solo. Even if you get into a teamfight it means you can lay down your Sanity's Eclipse on as many enemies as possible, and watch as they immediately change their mind and run away because you wiped out most of their HP with one click.

If you find you're at this point where you're a floating power house, the match can be your oyster. Orchid of Malevolence is a great pickup for the increased attack speed, extra Int and its superb silence which is great against casters. If you find you're taking a lot of damage from a right-clicker, Shiva's Guard offers some decent armour and Int, and offers even more utility with its active ability. However, it's worth noting that if you've got your Scyth of Vyse and you're already destroying the enemy team, it's worth trying to end the match as soon as possible. If your enemy is smart, they'll be building Black King Bars, and that will render your Arcane Orb useless, something OD NEEDS in order to dish out that massive damage. If they get magic immunity, you suddenly become far less of a threat.

If you find yourself being shut down in teamfights by a team that has a stable of disables, then it might be worth going BKB, however, if it's just a couple that are a problem, it may be worth going for Linken's Sphere instead, due to its stat gains. BKB's magic immunity is nice, but the extra damage isn't important on OD, and you gain more strength along with some HP and mana regen from Linken's Sphere.

Some people like to build a Refresher Orb on OD to double down on his Ultimate, but generally this is a bad idea. Refresher Orb is extremely expensive, and its stat gain is AWFUL and its mana regen is useless. Its only use on OD is for its utility, but what good is a two-shot of your Ultimate when you don't have the Int stat to make it truly effective? Build it only if you've got a ridiculously high Int stat, and you're owning the other team and you're bored.

Team Work

As you can guess, since OD is a hard carry, your main goal is to farm constantly, and to steal kills whenever you can. Your teamfight contribution in early game can be quite minimal; let your team initiate, stand back, and ready your Sanity's Eclipse to hit as many enemies as possible. If you've won the fight, and the stragglers are running away, trap them with Astral Imprisonment and you and your team mates should block their escape routes. Once they're free, finish them off with Arcane Orb. Other than that, NEVER initiate a teamfight.

Some players get cocky and think because their Ultimate stripped half the enemy's HP away they can stroll in and clean up, but they end up getting disabled and beat down by the team because OD is so damn squishy. A lot of what players assess when fighting against OD is how much damage OD is doing against them; if they realise he's hitting them like a truck, then they'll try to flee, but if they have a disable or nuke, they may realise they can burst down your health faster than you can them.

Get yourself to your Scyth of Vyse as soon as possible, and once you do, your teamfight contribution becomes significant, especially your ultimate. You still shouldn't initiate a 5v5, but lay down that Ultimate as soon as you can, on as many as you can, and you'll find you turn the tide almost instantly. OD has some high potential for dishing out insane damage, the faster you get that Int up the better, and the faster you become more of an asset to your team, but never get too cocky; you will always be squishy, and building strength and armour items on OD is more often than not a colossal waste of money because he NEEDS that Int more than anything.

Astral Imprisonment can also be a double edged sword. Whilst it's great for trapping a fleeing hero, interrupting a channeling skill (or even something like a Juggernaut Omnislash) or saving yourself from a nuke, it can also ruin your teammate's day. Many times have I seen an OD trap someone just before a Hook from Pudge was about to land or when a Sand King blinks in with a perfectly timed Epicenter and it can screw things up royally. In teamfights, don't just rush your trap, because that one hero who's causing the most hassle is probably the one your other teammates want to stun or nuke. If they burn their skills thanks to your poor timing, your team's at an immediate disadvantage.

Try to communicate to your team who you're going to trap, and try and go for the hero that has the most CC. If you can stop a Tidehunter from landing a clutch Ravage, then that's great. You can also use it to save allies; if you see they're going to get nuked or stunned, then quick fingers can move him to a safer dimension and they can return unscathed. Just remember, timing is everything, never rush your trap, it can make or break a teamfight.

In Conclusion...

Outworld Destroyer can be a complete beast of a hero, but he requires farm, patience, and timing. Never overstep your bound or overestimate your power, and never let games linger on too long when you're well farmed. I'll probably expand this guide over time, but if anyone has any suggestions to do with build, skills or strategies, please let me know and we can discuss it.

Thanks!