Please Help Me Triggering My Skill!!!

[Noudo]

I want to make the back stab damage shown in "Red" when using wind walk disapear...instead i want it to create a floating text that says Critical! on top of triggering unit

 

[canons200]

the damage windwalk shown in "Red" can't be eliminated, but what you can do is to create a floating text to "step" on the red damage.

 

[Laiev]

you can null it just seting damage of backstep to 0 and make everything else in trigger, like damage and floating text