Necrophos

Rotund'jere the Necrophos is a ranged intelligence hero. His abilities are most effective in team fights where he can damage enemies and heal allies simultaneously, while picking off key enemy heroes with his ultimate. Necrophos is most dangerous when his enemy is severely injured, instantly killing them with his ultimate while recovering over time after killing his foe. Necrophos is naturally fragile, but his mechanics require him to stay in the midst of encounters; it is for this reason that he depends on items to prevent his death. Ideally, by casting Death Pulse repeatedly, he and his team are able to stay alive while the enemy team's health is gradually sapped by Heartstopper Aura, which reduces enemy HP by a small percentage each second. Because his abilities are suited to prolonged encounters, he must build items which allow him to survive for as long as possible against his enemies. His ultimate, Reaper's Scythe, has its damage increased by how much of their maximum HP the target is missing; meaning that an enemy that is close to death will be killed outright by it. Upon attaining a kill, Sadist restores Necrophos's mana and HP over a short time, allowing him to continue fulfilling his role in encounters. Necrophos is best understood as a hero who is weak at the beginning of a fight but becomes more dangerous with each passing second.

Tips

 * in the early game allows to harass enemy heroes by simply standing near them. Its massive AOE will usually cause heroes to run out of their early game regeneration items quite fast.
 * Note however that the aura affects enemy creeps, and thus putting points in it will push the lane. Should you lane with a farm-dependent carry, it is unwise to push as it makes their farm more difficult and leaves both of you more vulnerable to ganks. Putting one or at the most two points in it is appropriate for early game.
 * If you're against a defensive tri-lane or playing as an Offlaner and the enemies in the lane lack disables, maxing first is a viable option if the enemy chooses to play passively. The massive degeneration will make it hard for the enemy to farm and in some cases they might ignore Necrophos until it is too late and their HP is low enough for a kill with  or make them vulnerable to a gank. The same can be said if you are in an defensive trilane and the enemy has a tanky offlaner.
 * If you're planning to go in the mid lane, you can skip the until level 10 if your enemy rushed their  and you think your team-mates cannot prevent your enemy from utilizing the runes. Putting skill points toward  instead will provide you with a good amount of sustain and will reduce the toll on your HP and Mana when ganking the side lanes assuming you got the kill.
 * Don't neglect to use basic attacks to harass the enemy during laning phase. already negates their regeneration or at least hinder it significantly if they bought/rushed HP regen items like  and  in anticipation. Even attacking them once in a while goes a long way because they can't readily recuperate the loss of HP and will eventually force them to use their consumables or retreat.
 * If you are going for an early push strategy, an early in conjunction with your aura will work wonders and will make the lane a battle of attrition that they will lose from either using too much regen items or being too afraid to last hit. Unless of course they have a naturally high HP regen.
 * Necrophos is countered in lane by any hero with high HP regeneration, such as and Quas-focused, or a hero with lifesteal capabilities; because he relies on inflicting constant, gradual damage with  and . Heroes with these attributes will resist this in lane against Necrophos, keeping high enough HP to prevent death by.
 * The philosophy behind is that (owing to ) it will return its mana expenditure if you secure a kill. There are several situations in which this ability should be used purely for its stun, such as interrupting channelled ultimates (such as those belonging to  or ) or preventing an enemy hero from escaping. Remember that the stun goes through magic immunity, although the damage will not.
 * At level 3, Reaper's Scythe will kill targets at 40% or less hp (with it's generally any amount under 45%). Remember to factor in Magic Resistance before you attempt to execute an enemy hero with it. Remember that this ultimate adds additional time to its victim's respawn timer and with Aghanim's Scepter it prevents them from buying back. In later stages of the game this can prove very important in removing key enemy heroes from the fight for a very long time.
 * The instant-kill HP threshold, with the base 25% magic resist factored in and without Aghanim's Scepter, can be calculated by multiplying the enemy max health with the constants: 3/13, 9/29, or 27/67 for each respective level of the ultimate. With the Scepter, the values change to 9/29, 27/67, and 9/19. Example: If  has 700 max health; 700*3/13 = 161. Id est, she must have 161 or less HP to be killed by level 1 Reaper's Scythe without Scepter.
 * Keep in mind that Reaper's Scythe is not a channeling ability, meaning you can move the moment you have cast it. As such, it can be used to escape ganks and chases.
 * Because you can cast during the stun, you can use it to initiate on an enemy hero to keep them from escaping or using assuming you can cause enough damage in 1.5 seconds. You can instant-kill with this tactic if you are paired with a high burst damage hero such as  or  or, or if you are in possession of a high level  and an
 * combined with an will greatly increase your chance at winning the match if it reaches the late game. If you manage to kill 2 enemy heroes in succession, the inability to use buy back and the sheer duration of their respawn time ((5 + 3.8 × (Hero Level)) + 30 + (25% of remaining time if buy back is used just before)) might be enough to decide the match, more so if the victims are key heroes in their line up.
 * If the situation permits, you should focus on using only on the same enemy (preferably the carry) throughout the match. The extension of the respawn time will add up and will cause significant reduction to the enemy's farm. To put it into perspective, if you manage to kill the same enemy hero twice, it will already make their farm a minute late more than usual if killed by anybody else. This will cause heroes who depend on snowballing early like  to become almost useless in mid to late game as their chance to snowball will be greatly reduced, or make the enemy carry under-prepared to tackle your team's carry hero.
 * can very easily be built as a tank and in most circumstances should be; you may gear for strength (he does not need excessive intelligence as his basic attacks are not too useful, and Sadist refunds mana for each kill he gets). The reason he is usually built as a tank is because he needs to stay alive in violent encounters to heal his allies (a good enemy team will focus him first), and also because the longer he is alive for, the more damage his aura will do and the better chance he has of landing a crucial.
 * Though it may be a bit wise to build some mana pool increasing items such as, Point Booster or other Intelligence items anyway, because if Necrophos has used all his abilities and failed to get a kill, he can wind up unable to cast any more of his spells, and if his auto attack is not too great, getting last hits to regenerate some mana can be problematic.
 * Utility items, such as, and  are more useful for Necrophos, because he can inflict constant damage with  simply by avoiding death and synergizes with his  to keep his team alive. In that sense,  is also a viable luxury item for Utility Necrophos as it will greatly increase his durability while also providing a useful team ability.
 * is a viable item for Necrophos because of his durability. This also synergizes well with making prolonged team-fights a dangerous prospect for the enemy team.
 * As Necrophos's survivability heavily relies on his ability to spam you need to be wary of heroes with silence such as,  and .  can also greatly cripple you with   as this ability prevents HP from regenerating for an extended period of time.
 * Necrophos is effective against invisible heroes that tend to stalk their prey as his does damage while they are in stealth, his  hits invisible units, and his Reaper's Scythe will prevent them from escaping via invisibility before they die. He is also very good against heroes with abilities that deplete their own HP such as, , and  ( is an exception since his Berserker's Blood will almost always prevent you from killing him with Reaper's Scythe), but Necrophos should first be durable enough to take on these kinds of risk/reward heroes.
 * Necrophos's role is notoriously debated; while his abilities appear supportive at their core, his  is a tool used to secure kills only for himself (much like 's Culling Blade). This is atypical for a standard support hero, because supports usually attempt to confer gold and experience to the team's carry. The duplicity of his carry/support role stems from his unique stance in encounters; his kit is largely supportive until an enemy hero grows weak, at which point Necrophos has the capacity to kill said enemy himself. He is best viewed as a utility focused semi-carry, rather than a full fledged support hero.
 * is more useful on Necrophos than other heroes because it not only deals burst damage, but also allows you to quickly deal more damage from your ultimate.
 * can be used in conjunction with and  to deal significantly more damage. If you are also in a possession of a high level, a quick Reaper's Scythe to Ether Blast to Energy Burst combo can decimate full health enemy heroes with total health points lower than 2000, assuming they have the standard 25% magic resistance. It is worth noting that Ether Blast temporarily increases the magical damage dealt per missing health from the standard ( 0.4/0.6/0.9 (0.6/0.9/1.2*) ) to ( 0.56/0.84/1.26 (0.84/1.26/1.68*) ) thus also increases the instant-kill threshold.
 * Assuming a level 5 Energy Burst and a level 3 Reaper's Scythe with an is used against an enemy with 25% magic resistance while being ethereal, you will deal 840 damage from Dagon and 1058.4 damage from Reaper's Scythe, to a total of 1898.4 damage (not including damage from Ether Blast and Reaper's Scythe damage due to it). If the match reaches the late-game, you still can burst down a full health non-magic-immune enemy carry with standard magic resistance during teamfights, potentially turning it into your team's favor.
 * Necrophos excels at sustaining Deathballs due to his . If he's able to build a, he can keep the pressure up at the enemy lanes and prevent the enemy team from farming. If you can get it early enough, you can choose to build it before and/or  because it will drastically improve your survivability and so that you can store enough charges.
 * could be built before Bloodstone if you plan to do a more offensive approach as your Death Pulse will heal for 130 + 50 per hero hit and reduce its cooldown to 3.75 seconds. If you also manage to kill an enemy with Reaper's Scythe, the massive damage coupled with the heal from Sadist will in some cases be enough to heal Necrophos from critically low health to full health. However it is advised that you build a Bloodstone afterward because the Octarine Core will increase your mana consumption and is a lot less effective than Bloodstone at restoring mana.

Trivia

 * Necrophos's response, necr level 04.mp3 "My name is lesion!" probably has to do with the Bible passage Mark 5:9, that reads in the NIV, "Then Jesus asked him, 'What is your name?' 'My name is Legion,' he replied, 'for we are many.' "
 * Necrophos's response, necr ability reap 03.mp3 "You reap what you sow." might be from the Bible's passage Galatians 6:7 "Do not be deceived, God cannot be mocked. You reap what you sow."
 * Necrophos's response Necr attack 14.mp3 "Red Death." may be a reference to the Edgar Allen Poe short story of the same name.
 * Necrophos's alternate/fun name was "A Phoe Gyi", which means "an old man" in the Burmese language. It also sounds similar to 'a fogey', which is an elderly, normally grumpy individual.
 * Necrophos's original title in DotA was "Necrophiliac"; his designer altered the name to "Necrolyte" (a portmanteau of nekros (νεκρός), the Greek word for corpse, and acolyte, a religious attendant) upon realizing its implied sexual connotation.
 * In the November 21, 2013 update, Necrolyte's name was changed to Necrophos, likely to avoid copyright issues with Blizzard. As phos (φῶς) is the Greek word for light, it might be a pun on the misreading "Necrolight" of his former name.
 * In the same update, extra filters were added Necrophos's voice, along with a 10% higher pitch, to make him sound more distinct from . However, (most likely) a typo caused his voice to be played at 10% pitch, instead at the desired 110% pitch, causing his voice to be much deeper and slower than intended.