[GAMEPLAY] Yasuo's Q Can be Cast During his Ultiamte

In short, with any degree of reduced cooldown (or following up on a friendly knock-up) Yasuo can cast his Q during his ultimate, Last Breath's, animation. If done in this way it does not provide a visual cue that the spell has been cast for friendly or enemy, as far as I am aware cannot be interrupted (haven't tested this), and deals full damage.

This does not seem to be an intended interaction, as it is not listed anywhere in the tooltips of Yasuo's kit, nor does it display an animation of any variety when performed, just dealing extra damage during his ult and stacking his Steel Tempest.

This is a bit of a second-hand report, as I while I have experienced this in-game, I was not aware of it being a reproducible occurrence until I saw it explained as a strategy in Trinimortal's "The Only Yasuo Guide You'll Ever Need." As such, here is a link to said video, timestamped to just before he explains this bug and how to reproduce it. Not exactly a complicated explanation, so I'll copy it here.

When the target is knocked up by either your Q's third proc or another knockup, wait until you've got the spell mostly off of cooldown (attack speed makes this easier, naturally)

Activate your ultimate, Last Breath, to suspend the target

During the animation, cast Q again to get the damage of both Last Breath and Steel Tempest.

I had been victim to it in the past but was unaware that it was reproducible until now.

Again, this does not SEEM intended, but it could be? I could see no good reason for it to be an intended interaction as there's no good reason why Yasuo should be able to cast during his ultimate where almost no similar situation exists in-game: Malzahar and Warwick can cast summoner spells during their suppression ultimates, but outside of I believe Warwick's two non-damaging abilities, casting their Q or other damaging abilities will interrupt their ultimates and end the effect and damage therein. Likewise with any other channeled abilities. While Yasuo's ultimate is not channeled (it cannot be interrupted by anything short of death, though it can be cleansed), it would be the only instance where a sustained lock-down ability can be interrupted to cast a damaging ability without interrupting the crowd control, nor the damage at the end of the ability.

I hope this is useful, or if it is intended, that the tooltips can be adjusted to reflect its existence as a legitimate part of Yasuo's kit.