The book came out on November 1st.

What is the title of book 16?

So far, the others (we think) are not Nathan, Doom, Buck, and Delores.

Delores Gristlewurst (Tiffany Fluffit if you didn't know)

DREAD OVERLORD SPLAARGHON! DIDDLY WIDDLY DIDDLY WIDDLY DIDDLY WIDDLY SQUEAL

Yes the good guys club found him in book 7.

mr piranha is a bolivian piranha that public calls a mutant sardine