I think Specter of Torment is still better, but King of Cards was really fun and a nice send-off to the series. King Knight is very fun to play as, being this glass-cannon character who's sort of a fusion between Wario and Shovel Knight. The level design is some of the best in the series, and there are way more levels in this installment compared to the other three (At the cost of the levels being way shorter). The bosses are really good as well per usual. Granted, about half of them are directly lifted from Specter of Torment with minor changes (Like Plague Knight's fight taking place during a vertical autoscroller and Polar Knight summoning Spinwolves to assist hm), but the rest are either completely new bosses (i.e. the Troupple King and Cardia) or revamps of older bosses in the series (i.e. Specter Knight and Mr. Hat), and they're all really fun. The soundtrack is good as usual, but a lot of the songs are returning ones from one of the previous Shovel Knights installments and most of the new ones are relegated to Joustus. Speaking of Joustus, I really like it. It's really addictive, fun, and even intense at times, and the fact that there's about 140 Joustus Cards means you can come up with all different kinds of strategies and combos. It reminds me a lot of something like the various versions of Skystones from Skylanders, just more refined, balanced, and with better AI. Plus, if you're not a fan of Joustus, it's completely optional towards beating the main story, so that's really cool.
Most of my issues with the game are just minor nitpicks, like how the story feels underwhelming compared to Specter of Torment's (Though unlike Specter of Torment, it does a much better job at wrapping up a ton of loose ends from Shovel of Hope/Plague of Shadows like how the Hedge Pupil lost his house keys, how Mr. Hat ended up in the Armored Outpost, and where the ghosts from the Hall of Champions came from) and how I really wish Joustus had online multiplayer, but for the most part, I really liked King of Cards. It's not as good as Specter of Torment, but it proudly takes the #2 spot.
Most of my issues with the game are just minor nitpicks, like how the story feels underwhelming compared to Specter of Torment's (Though unlike Specter of Torment, it does a much better job at wrapping up a ton of loose ends from Shovel of Hope/Plague of Shadows like how the Hedge Pupil lost his house keys, how Mr. Hat ended up in the Armored Outpost, and where the ghosts from the Hall of Champions came from) and how I really wish Joustus had online multiplayer, but for the most part, I really liked King of Cards. It's not as good as Specter of Torment, but it proudly takes the #2 spot.