Answer:
Being able to interpret the letters on this screen proves that you have this quality.
With pointed fangs it sits in wait. With piercing force it doles out fate, over bloodless victims proclaiming its might. Eternally joining in a single bite.
Three little letters. A paradox to some. The worse that it is, the better it becomes.
If I have it, I don't share it. If I share it, I don't have it. What is it?
What do you use to hoe a row, slay a foe, and wring with woe?
When is it bad luck to see a black cat?
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?