DotA2 Skill: Duel

Duel

Casting Method:	Active
Targetting Method:	Unit
Allowed Targets:	Enemy Heroes

Legion Commander and the target enemy hero are forced to attack each other for a short duration. Neither hero can use items or abilities. If either hero dies during the duration, the hero winning the Duel gains permanent bonus damage.

Duration: 4 / 4.75 / 5.5 * ( 6 / 7 / 8 )
Duel winner bonus damage: 10 / 14 / 18
Range: 150

You and your target are immune to all damage unless the source is between the Duel participants while the Duel lasts. Increases duration. Legion Command is spell immune during the duration of duel.

Mana Cost: 75 Cooldown Time: 50

Additional Information

To face a soldier of Stonehall in single combat is a challenge few can resist.

Notes:

The loser of the duel is the hero that dies while under the buff. There is no victor if both heroes are alive at the end of the duration, and no damage bonus is granted.
Both Legion Commander and her opponent are muted while under the effect of Duel: They cannot cast spells, use items, and most passive abilities are disabled. lts cannot be disarmed or Force Staffed away.
Legion Commander will ignore effects that disable her attacks during Duel such as Frostbite if Duel is activated after being disabled. however casting a Frostbite while the Duel is occurring will prevent the target from attacking.
If the opponent being killed is holding an Aegis of the Immortal or is Wraith King with an active Reincarnation the Duel is won regardless of them coming back to life, However the same is true for Legion Commander (if she dies holding an Aegis of the Immortal she will give bonus damage to the opponent as well).
Legion Commander's opponent does NOT get the bonus damage if she dies whilst under the effect of Disruption or Astral Imprisonment. However , Legion Commander receives bonus damage if her enemy dies while she was banished.
Legion Commander will not gain bonus damage from defeating Illusions but will grant an illusion bonus damage if defeated by one.
Ethereal units can be targeted for Duel, but won't take any physical damage for the duration of the ghost form. However, they will regain ability to attack while the ghost form is on. It's currently unknown if it's intentional.