Controls:
WASD or Arrow Keys to move
Space, E or Click to shoot out your tongue

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Eat flies to get big.

Eat frogs to get bigger.

Become a parasite to the big frogs to steal their mass by latching onto them with your tongue.

Only certain types of frogs can eat others:

Big-tongued frogs eat big-eared frogs.
Big-eared frogs eat googly-eyed frogs.
Googly-eyed frogs eat big-tongued frogs.

if you forget, you're toast.

It is possible to become the last frog standing. I have done it before and I challenge you to do the same.