Pokemon Trainer that gave you the most trouble

Which Pokemon Trainers were a pain in the ass for you to defeat? Did you have to use multiple full restores/revives, or did you lose altogether and have to restart the fight?

Discuss.

A lot of them were nameless tbh.

Since I do not remember most Pokemon trainer names, I'll name the gym leaders and Elite 4 members that were a pain in the ass for me for the first 2 generations of games:
- Red/Blue/Yellow: Erika, Sabrina, Giovanni, Lance and Gary/Blue.
- Gold/Silver/Crystal: Whitney (I still remember her stupid Miltank and her Rollout attack), Clair (Slightly), Gary/Blue, Lance (Again) and Red.

Whitney.

Brock in Yellow.

Oddly enough, Bianca always gave me more trouble than cheren.

Also there is always an ace trainer on victory road who hss a muk that knows minimize. I hate that guy.

You could have trouble with trainers? O_o

Usually, I just steamroll through everything.. Maybe I'm just lucky enough to pick good skills (Never was ocd enough to check the competitive oriented sites, I always played cold..)