Holliday can use 3 spell on ult Viscous and she won't be stunned.

[sibase💖]

Holliday can use 3 spell on ult Viscous and she won't be stunned. It would be more logical if you entered the "stunned" state

 

[dancedanceincineration]

nah this is intentional
viscous's goo ball hitbox is disabled when he's stunned

 

[🐸mr.rukolo🐸]

That not a bug.
Only Torment Pulse and Warden ult works in Holliday ult works, I think