Hippopotamus


 * Whiff's Voice Suits Hippopotamus.

Episodes
=F= =M= =O= Season 14 - and O the Indignity Season 15 - Spencer the Grand, Kevin the Steamie (cameo), and Fiery Flynn (cameo) Season 16 - Thomas and the Rubbish Train, Percy and the Calliope (cameo), Sodor Surprise Day, and Whiff's Wish Season 17 - Scruff's Makeover and The Frozen Turntable (mentioned)
 * Flamingo's Rubbish
 * Monkey and Cougar
 * Owl's Special Surprise