Terrorblade

Terrorblade is a melee Agility Carry with a focus on a limited amount of powerful illusions. As with any illusion based hero, he requires stats-based items to make his illusions as strong as possible. His unique ultimate allows him to swap his health bar with another hero making ganks on him dangerous without extended lockdown to keep him from casting it. He can create long duration illusions of himself that deal a significant amount of his own base damage and a powerful slow that creates unattackable illusions of all nearby enemy heroes that deal a significant amount of their base damage. His third ability is a potent long duration transformation spell that makes him a powerful ranged damage dealer. He has high starting armor but low starting health making him particularly vulnerable to early game spell damage.

Tips

 * Ethereal Blade is an underused but effective item, providing a hefty 40 agi + 10 str at 4700 gold. The active nuke is also extremely powerful as a finisher, in conjunction with Sunder and Terrorblade's high agility gain.
 * Satanic could be considered as an alternative to Heart of Tarrasque provided you can deal enough damage for the lifesteal to be effective. If Sunder is currently on cooldown, Satanic's active can be considered an alternative to it as it can very easily refill your entire health bar. However, beware that Satanic also acts as a strong way of countering Terrorblade himself in a one-versus-one as the person who you are up against can activate Unholy Rage right after you have used Sunder on them, effectively making your ultimate pointless.
 * A Blink Dagger allows you to initiate with Reflection/Sunder and hopefully kill lone targets without the help of an ally. It also provides you with a much-needed escape.
 * While Sunder is most often used to save yourself from death or nuke an enemy carry, it can also be used to save allies. However, since Terrorblade often serves as the team's main carry, leaving yourself with very little health can be a game-risking mistake.
 * Terrorblade's item builds are versatile, and can range from an early/mid-game oriented build such as Ring of Aquila, Drum of Endurance, and Sange and Yasha, to a more conservative late game build such as a Linken's Sphere rush into Manta Style (similar to how you can itemise or ).
 * Terrorblade's extremely high armor allows him to trade auto-attacks and tower dive with impunity in the laning phase, especially when combined with a Poor Man's Shield. However, the trade-off is his low health pool which makes him very susceptible to nukes such as Finger of Death or Laguna Blade.
 * Shadow Blade is a great initiation and escape item, which also allows you to get close enough to your enemy and use Sunder with minimal risk. It also provides great damage and attack speed, both good attributes in all stages of the game. Keep in mind though, that none of the bonuses from Shadow Blade benefit illusions.
 * Terrorblade excels at split pushing in the mid and late game, where he can summon up to four Metamorphosed illusions with a Manta Style. Additionally, Sunder allows you to dominate any one-versus-one fights with heroes who don't have enough lockdown to prevent you from casting it.
 * With enough points in Conjure Image, Terrorblade can become an efficient jungler who can clear multiple camps with reasonable speed.
 * While laning, use your illusions to stack the jungle for yourself. Then once the laning stage breaks down, you can use Metamorphosis to clear jungle stacks, thereby increasing your GPM.
 * When appropriate, farm the jungle with the main Terrorblade while micro-ing Terrorblade illusions to farm in lane to boost your GPM.

Trivia

 * In DotA, Terrorblade and were brothers. This was to be kept in Dota 2 based on certain responses Anti-Mage made in Terrorblade's presence, but upon Terrorblade's release, these relations were severed and thus the lines went unused.
 * Terrorblade's title in DotA was Soul Keeper. Unlike other name changes, this one does not appear to be related to copyright issues with Blizzard. It is speculated that the name was changed to avoid conflicting abbreviations with Sand King.
 * Another reason could be that the title "Soul Keeper" doesn't fit him anymore, since only one ability could be associated with souls. In earlier versions, he had a second ability called "Soul Steal", which was basically a life drain without channeling.
 * In-game, Terrorblade constantly leaves flaming footprints wherever he goes, similar to his DotA hero model, Illidan Stormrage (a prominent Warcraft character), who also leaves flaming footprints. These can be seen by enemies, but stop being rendered once he's out of their vision, meaning that one cannot track down an enemy Terrorblade that goes invisible or enters Fog of War on the basis of his footprints.