Mercurial the Spectre is a melee Agility hero adept at dealing pure damage to lone targets and is powerful, both offensively and defensively. Spectral Dagger provides her with a significant amount of mobility, allowing her to pass through objects, units and terrain while slowing her foes that came in contact with the shadowy path left by her Spectral Dagger. Desolate allows her to inflict high pure damage to enemy heroes when she catches them alone. Dispersion reduces and reflects all damage, whether by attacks or spells, to an area around her as pure damage. Dispersion gives her great durability, especially when equipped with items that provide health, armor, and damage block. Finally, her Haunt creates a malevolent spectral illusion to all enemy heroes in the map. Haunt lets Spectre wreak havoc in clashes and ganks, while her allies take advantage of the confusion. Spectre can use Reality during the Haunt, instantly teleporting her to her illusion to take its form. This lets her hound her victim anywhere on the map. Mercurial is a dangerous supernatural being, relentless as she can chase and stalk down her victim to a global range, unhindered by boundaries. Her kit allows her to play the role of the team's hard carry by applying an immense amount of pressure in late game team fights. More specifically, the pure damage reflection from Dispersion makes it disadvantageous for teams to focus her. Her abilities have a complex nature, and newer players should generally not play Spectre as she is extremely farm and level dependent. It is best to face Spectre with allied help and strength, as encountering her alone isn't always the best option.
- Spectre's strength lies in her ability to participate in teamfights from anywhere on the map using her ability Haunt, as well as her ability to leverage HP better and damage supports more readily than most agility carries. Her illusions created by Haunt receive Desolate. It is wise to get items that add additional passive abilities that are usable by illusions.
- Diffusal Blade is the only Unique Attack Modifier that works on Spectre's illusions, as well as providing an agility bonus that will indirectly increase illusions' damage along with a purge. Illusions will also benefit from Radiance's Burn Damage, Daedalus's critical strike, and Sange and Yasha's movement speed, attack speed, strength, and agility. Butterfly gives a lot of agility. A common misconception is that the evasion stat will "reduce" the damage from Dispersion, but this is not true. By going from 100% HP to 0% HP, Mercurial will disperse exactly 28.2% of her health at max rank. For the same reason, spell resistance and armor do not reduce the damage dispersed, instead only increasing the amount of damage needed to reduce her HP to 0. This lets her leverage her autoattack, AoE damage (Mjollnir, Radiance), lifesteal, or regen to deal more damage and drag the fight on for longer. Heart of Tarrasque or Eye of Skadi gives her a great deal of HP, which makes Dispersion more powerful.
- Since Spectre's illusions are very powerful (due to Desolate and the passive abilities of the items she acquires), Manta Style can capitalize on this advantage by making even more illusions, as well as giving bonuses similar to those of Sange and Yasha. While it is tempting to level Spectre's ult to level 3, the points are often better put in stats, 2 levels of stats gives her more hp, better armor, more damage, faster attack speed, and boosted mana regen. Having her illusions for 2 more seconds may not be as useful as beefed up stats.
- Tranquil Boots provide Spectre with much needed lanestaying power without committing to a full vanguard. The movespeed bonus also benefits haunt illusions, as they do not get the active from Phase Boots.
- Mjollnir adds significant farming and push potential, while filling the AoE damage role of Radiance while also scaling better and having an easier buildup. However, illusions get no benefits from it.
- Eye of Skadi provides great general stats, solves Spectre's mana issues, and gives her a BKB penetrating slow that lets her chase and forces attention on her. The early orb of venom and point booster give Spectre great early presence.
- Skull Basher adds some damage and HP along with BKB-penetrating anticarry and chase potential that again forces attention onto her.
- Pipe of Insight makes Spectre incredibly tanky against magic damage when combined with dispersion (combined 57% resistance), and increases her teamfight presence with the HP regen and active ability.
- Armlet of Mordiggian has incredible synergy with Spectre's skillset. The HP and offensive bonuses work with dispersion and desolate respectively, which also transfer to her haunt illusions. The passive regen fills the need of a vanguard for her core, while armlet toggling provides increased HP for Spectre to disperse.
- Assault Cuirass adds extra durability and makes haunt a global -5 armor for the duration while giving any teammates in range extra armor and attack speed. The attack speed has good synergy with desolate, but does not transfer to illusions.