It took a true 'How I Met Your Mother' fan to remember that Barney (Neil Patrick Harris) always considered William Zabka to be the true hero of 'The Karate Kid,' but we'll have plenty of time to learn in the final season! After a season 8 cameo, Zabka has been revealed to return for a surprising number of episodes in the final 'How I Met Your Mother' run, but what other surprises are in store?

Though producers supposedly hoped to keep Zabka's reappearance under wraps, series star Cobie Smulders took to Instagram with a photo that revealed the true 'Karate Kid' on the set. Surprisingly, Smulders was photographed wearing her "Robin Daggers" getup, which could suggest either Robin knew Zabka in the '90s, or decided to spend part of her wedding weekend reliving her musical career.

Zabka made a surprise appearance in last season's bachelor party episode "The Bro-Mitzvah," hiding in plain sight as a clown while Ted and Marshall invited along Zabka's 'Karate Kid' co-star Ralph Macchio, until Zabka revealed himself at the very end. This time around, EW reports that Zabka will appear in at least eight episodes of the final season, having become Barney's friend and presumably taken some involvement with the wedding.

Meanwhile, the final season of ‘How I Met Your Mother’ has recruited other such guest stars as ‘True Blood‘ star Anna Camp (replacing ‘The Office”s Ellie Kemper), ‘Revenge‘ star Roger BartSherri Shepherd, and Wayne Brady and John Lithgow reprising their roles as Barney’s half-brother James and biological father Jerry. In addition to clarifying the final season’s wedding weekend format and releasing new promos, clips and photos, CBS previously revealed that all four regulars would meet the mother prior to Ted.

Well, what say you? What other past 'How I Met Your Mother' guest stars would you want to see return for the final season? Check out Cobie Smulders' photo above, and give us your predictions for September 23 premiere "The Locket / Coming Back" in the comments!