If you want to make the Pact Blooms build,
Go to Custom Unit Builder, select Sonia and once you select the weapon, Pact Blooms will be there.
Why it is there and not in the regular builder is as a big mystery as IS not giving Sonia a prf.
This is the build I’d like to run on mines (minus the S-support), I’d pick Null Follow up 3 to take on Impact users and Forced units better but Lull might be better for extra bulk. With some drive/guard support, she can hit hard and be bulky in both phases. It’s more reliable.
If you want spd, you need invest quite a lot in her and while Brunnya can do it better, Sonia can still do it just fine.
About 64 spd and she remains bulky and hits hard.
I think the Spooky Censer works with Desperation and Brazens