wels has been done, Afro lungs could be done, like fished for. candiru asu are def monsters, he did p's with out catching a rhom for god sack so why not do candiru if u want something thats dangerous! aus and the mighty Wallagu... I'm also guessing there are a lot of large catfish sp around the world we are not so aware of that could feature too... ie central and west africa, central asia ext...
and for that matter unless im mistaken ive neve read a report of a giga being exactly dangerous to a human?