Nagäae

Nagäae have toad-like, transparent bodies, their pulsating innards covered only by a thin layer of leathery skin. They have the hind legs of a frog, and four forelegs of a man. Their face consists mainly of bulging eyes and an oversized mouth with two forked tongues. They are amphibious, found all around the world, and serve Cyaegha, sharing their sire's malevolence.

In the RPG...

The Nagäae have a poison in their bite which has a 98% chance of killing an average human. However, it may also choose to render them unconscious for an average of 10 rounds (presumably for later consumption). If the victim succeeds in an Extreme CON roll, they will only suffer mild hallucinogenic effects and take a Penalty Die on all skill rolls for an average of 10 rounds. Nagäae are also pretty deadly, even without this poison, as they get 4 attacks per round which each average 10 damage, as well as having 23 hit-points and 2-point armor.

    The only stat changed for the 7e Malleus Monstrorum is the Nagäae's SIZ. The average remains the same, but has been given more range. 

In a video game...

I think the Nagäae would be pretty cool in a video game, though as with the other poisonous beings on my list, their insta-kill venom would not be much fun.

In a film...

Because of their frog-like appearance and human-like arms, it would be a very fine line between scary and laughable with these creatures, so you would need a competent FX team to do them justice.