What illusions are
An illusion is a controllable copy of a hero created by an ability (Manta Style, illusion rune, skills like Naga's or Phantom Lancer's). Visually it's nearly indistinguishable from the original, but it's actually a separate unit with its own rules.
- Copies look and stats. The illusion looks like the hero and takes its base stats.
- Its own damage multipliers. It deals less and takes more — exact numbers are set by the source.
- Doesn't cast. Illusions don't use abilities or active items, but inherit some effects.
An illusion isn't a second copy of your damage — it's a tool for pressure and deception. Value it for the confusion in fights and lane pressure, not as a "second hero".
How much they deal and take
The key points about illusion damage come down to a few rules:
- Deal a fraction of the damage. An illusion hits for only a share of the hero's damage — the exact percent is set by the ability or item that made it.
- Take increased damage. Incoming damage on an illusion is multiplied, which is why it dies faster than the original.
- Weak vs buildings. Only 40% of an illusion's damage goes through to buildings, and under backdoor protection it loses 75% instead of the 25% any other unit loses. Against Roshan just 20% lands.
- Give little on death. The bounty is twice the illusion level in gold and the same in XP, and the XP is only granted when a hero lands the kill — an expiring copy, or one killed by lane creeps, gives the enemy nothing. Creeps you last-hit with them are credited to you.
Take Manta Style in patch 7.41f: two images for 18 seconds on a 34-second cooldown. A melee hero's images deal 33% damage, a ranged hero's deal 25% (28% before 7.41f), and they take 300% damage.
So pure illusion split-push is slow — it's sped up by aura items, covered below.
Which items work
Some items carry over to illusions, some don't, and that decides their usefulness:
- Carried over. Crits (Crystalys, Daedalus, Coup de Grace), lifesteal (Morbid Mask, Mask of Madness, Satanic), the Vladmir's Offering aura and stat bonuses from Manta Style — copies use all of these.
- Not carried over. Diffusal Blade mana burn, Battle Fury cleave, Skull Basher and Abyssal Blade bash, Desolator armor reduction, Maelstrom and Mjollnir chain lightning, Eye of Skadi slow. From Monkey King Bar an illusion takes the accuracy against evasion only, never the bonus damage.
- Radiance. Every copy carries the burn aura, but it burns weaker: 35 damage per second instead of 60. Auras do not stack — only the strongest burn counts on a given target.
- Active items. Illusions don't press actives — BKB, blink and similar won't trigger on them.
Radiance is picked on illusion heroes not for the damage total: auras do not stack, and only the strongest burn ticks on a target. The value is coverage — every copy carries the burn to its own part of the map, so the copies clear camps and pressure lanes while the hero is busy elsewhere.
How to use copies
Illusions are useful far beyond "add damage": their main value is making the enemy spend crowd control and focus on the wrong hero.
- Confusion in fights. The enemy wastes control and focus on copies while the real hero works.
- Split-push and farm. Copies pressure side lanes and stack camps, freeing the hero.
- Scouting. An illusion is expendable for checking a rune, Roshan or approaches.
- Baiting initiation. An illusion eats the combo first, and you see the enemy's cooldowns.
An experienced player "plays" illusions separately from the hero — a skill that markedly raises core-role effectiveness and helps you climb MMR.
Common mistakes
These slips turn illusions from an advantage into lost tempo:
- Treating an illusion as a full hero. It does copy crits and lifesteal, but not bash, cleave or mana burn — and its damage is still a fraction of the original's.
- Bunching all copies under AoE. One Crystal Maiden ult or an Eq, and the swarm vanishes for nothing.
- Expecting copies to take a tower fast. Illusions deal 40% to buildings and three times less than a normal unit under backdoor protection — without creeps they will not push it down.
- Giving yourself away. Move the hero and copies differently, or the enemy spots the original instantly.
