How I Met Your Mother came out strong with a solid first season, but it wasn't the highlight of the show's run. From the second season onwards, the sitcom truly reached its potential. And plenty of credit should be given to the characters the series added.
Some of the funniest and most interesting people didn't appear until the debut year was over. Several of them became recurring figures, while a few just turned up for a handful of episodes. Yet, these characters' impact on HIMYM was substantial.
Steve 'The Blitz' Henry
The Blitz only appeared in two episodes of the series, with the second being a cameo. However, the character made a big impression in his limited screen time. From his incredible spells of bad luck to his chirpy attitude, Steve was always entertaining.
He was incredibly witty, too, as he had countless funny lines during the "Blitzgiving" episode. For example, "did they tell you about the skateboarding dog ... it was awesome," which was made more humorous by Jorge Garcia's excellent delivery.
Quinn Garvey
As far as Barney's girlfriends go, Quinn was one of the best. She entered the show partway through season seven and had great chemistry with Stinson. She was cool, fiercely independent, and deceitful.
"Deceitful" would usually be a negative trait, but as Barney had been tricking women for many years, it was nice to see him get a taste of his own medicine, and the two of them made for a fun pair. In fact, it would've been nice if the couple had been together for a little longer.
Nora
Nora was a recurring character during the sixth and seventh seasons. She was an important figure in the development of Barney as her unwillingness to put up with his lies forced him to be a better man, and she was a more positive influence on him than any of his other exes, even Robin.
Their relationship made for some excellent and emotional episodes. However, Nora was more than just Barney's girlfriend. The woman was likable and very funny in her own right.
William Zabka
Celebrities playing warped versions of themselves are usually one-episode things, but William Zabka featured in seven. He didn't overstay his welcome, though, as he was a constant source of entertainment. Jokes about his career as a bad guy and his surprisingly cultured tastes were great.
Plus, his whole friendship with Barney was a joy to watch. And it served as a brilliant pay-off to the running gag of Stinson thinking that the villains in every movie are actually the heroes.
Patrice
HIMYM characters don't get much more lovable than Patrice. Robin's co-worker entered the series in the seventh season and stuck around until the end. Her continually upbeat and wholesome attitude made her very likable. Plus, she was arguably the nicest person in the entire show.
It's fair to say that she's most remembered for the running gag where Robin screams at her. Those moments wouldn't have been nearly as hilarious if it wasn't for Patrice's outrageous positivity before the screaming occurs or her funny facial expressions afterward.
Randy Wharmpess
Watching someone continually mess up isn't good in real life, but it's funny in the TV world. Randy Wharmpess was HIMYM's resident screw-up during his two appearances in the show and his awkwardness with women and clumsiness at work was hilarious to watch.
He also said some truly outrageous things while failing miserably, including claiming that a koala's meat is delicious while chatting up a woman. The guy deserved more episodes, but he was the highlight of the ones in which he did feature.
Brad Morris
Marshall's lawyer friend Brad was a recurring figure in the second season and then made multiple guest appearances for the rest of the series. Brad wasn't always the most likable secondary character in How I Met Your Mother, as he screwed over Marshall more than once.
Yet, the man's entertainment value can't be denied. Whether he was calling Zuzinni bread "redonkulous" or starring in a sexually charged video about a lake, his scenes were often memorable.
James Stinson
When introduced in season two, James and Barney had almost identical personalities. Their similarities could've caused issues, but James' transformation into a family man made him unique. Plus, it contributed to Barney's arc, as it was an early sign that the younger Stinson could also settle down one day.
James wasn't just there to help tell Barney's story, though. He had his own relationship problems later in the series, and he was an entertaining character, too.
The Captain
The Captain was a beloved member of How I Met Your Mother's supporting cast during the later seasons. His main personality trait was his obsession with boats and sailing, and his common use of boating expressions was a consistently funny running joke.
The man was also known for being incredibly intimidating without actually meaning it. Marshall even figured out the cause of his threatening demeanor in the iconic eyes vs mouth scene. There haven't been many characters like The Captain in sitcom history, which is what made him so special.
Tracy McConnell
After the first season, Tracy McConnell was the only true addition to the main cast. As the mysterious mother, she had a lot to live up to because Ted had been talking about how great she was for eight seasons before she entered the show.
However, the witty, smart, and sweet Tracy exceeded all expectations. She was arguably the best part of the last season, as fans fell in love with her just like Ted did. In fact, one of the biggest reasons people hated the show's ending was because she wasn't in it.