Can Ezreal's Q trigger multiple times with Iceborn Gauntlet?

Question

Ezreal's Q is as follows:

Ezreal fires a bolt of energy in a line that will deal physical damage and apply on-hit effects to the first enemy it hits. If it strikes an enemy unit, all of Ezreal's cooldowns will be reduced by 1 second.

If I hit multiple enemies due to the iceborn gauntlet, will it deduct 1 second of cooldown for every minion hit?

Answer 1

Unfortunately, that's not how the logic works.

Instead, it behaves like this:

  Did Q hit *any* enemy?
  -- Yes -> Reduce Cooldown by 1
  -- No  -> break;

For this same reason, a Nasus who kills multiple minions with his Q (due to Tiamat or Frostborn Gauntlet (or both!) ) will only power up Siphoning Strike by one minion's worth of damage.

Answer 2

No, because Mystic Shot's tooltip reads like this:

Mystic Shot - Active: Ezreal fires a bolt of energy in a line that will deal physical damage and apply on-hit effects to the first enemy it hits. If it strikes an enemy unit, all of Ezreal's cooldowns will be reduced by 1 second.

You hit an enemy, so it gets reduced by a second. If it was cumulative, it would say something like "cooldowns are reduced by 1 second for each target hit" or something similar.