Just my own funny little [Hirudo] build. It's expensive (omni and 6 normal formas) & there are probably better ones out there but it's also really fun to play.

If you want, you can go for normal [Organ Shatter] instead of Amalgam for more DPS but i like having the Wind Up Speed on mine.

Also if you don't use [Grim Fury] but [Brutal Tide] instead you can save the Stance Forma. I just like [Grim Fury] more since you can stack combos faster.

EDIT: now that the Coda Hirudos are out i'll work out a new build but i have to acquire them first.
EDIT2: Build is ready