Leech was by far the most underused of the Evil Horde villains. Even though Modulok made fewer appearances, at least that particular character was fleshed out! The simple fact is that Leech was the Tri-Klops of the Evil Horde; a character that the writers could do little with. Even though he had little screen presence, his suction cup hands made him unforgettable. It is worth mentioning that in his debut appearance in "Into Etheria" he displayed the ability to change between his suction cup hands and a pair of quite normal hands! Sadly, the character was so rarely used that we never got to see this again.
(click on the images to see them at full-size)