Answer:
Gets rid of bad ones, short and tall. Tightens when used, one size fits all.
What is up that’s also down? What’s a smile and a frown?
Long and slinky like a trout, never sings till it's guts come out.
In the forest, this blends in just right, but every December it is covered with lights. What is it?
Large as a mountain, small as a pea, Endlessly swimming in a water-less sea.
What sphinxes employ and players enjoy.
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?