opposer (noun)

1. The horror movie protagonist faced a formidable opponent, an evil opposer who tormented them throughout the film.

2. In the cartoon series, the brave protagonist always had to overcome a cunning opposer who tried to stop them from achieving their goals.

3. The architect's innovative design proposal faced strong opposition from the traditionalists in the field, making them a notable opposer of new ideas.

4. In the anime series, the protagonist engaged in intense battles with a powerful opposer, testing their strength and determination.