the increase to her stats only applies to her alternate form, so you will need to transform her to benefit from that. however, it is based on the number of debuffs placed altogether, so debuffs placed in her base form will still be counted. for example, if you placed ten debuffs in her base form and then transformed her, she would enter her alternate form with an additional 20% hp, atk, and def and 20 speed.

One of these days I will get my first Myth champ and learn about transformation.  

Karnage and Mikage are free.  😃 

Thanks for the help. I'm excited to get a lucky pull, but I'm very confused about how to use the champ. This is very helpful

Yep.  Still the only Mythicals I have after 133 Primals pulled.

I wonder if I will pull a Mythical before I earn the new one from Chimera.

Hopefully.  Even more Hopefully it's usable. 

One of the clan leaders in my cluster just opulled his first non-mikage mythic

....and got Ashnar. Who is ...kinda okay for Hydra. I suppose?

Unfortunate, hes definitely one of the weaker ones.

On Primal #144, I got Arbais, so I didn't have to go all the way to mercy (and beyond) for my first Mythical, and while she wouldn't have been my first choice, she is a pretty solid Mythical.

Shes quite good.  I have her on both accounts.  She's also really strong in Chimera now.