The final day of the Scripps National Spelling Bee could feature the most difficult words ever used in the competition.

Bee organizers decided to make changes after the competition ended in a tie the past two years. This year, the final three spellers could be forced to spell more, and judges can adjust the difficulty of the winning words as needed.

Also, the bee got rid of a second written test that was used to help pare the field down to 10 finalists. That means Thursday's morning rounds will be as difficult as necessary to eliminate 35 spellers.

Three spellers who finished in last year's top 10 remain in the bee. The winner gets more than $45,000 in cash and prizes.