Kamen Rider W (2009)

OOO is the series after W so if you want to watch the Kamen Rider seasons in order watch OOO after W.

They're Kamen Rider series that has the primary Kamen Rider as a detective and involve them solving case that involves the antagonists. The main characters of each series are very well liked and brings a very cool or should I say hard-boiled feeling to them.

No spoilers but everything related to Ruan Lanzhi's character is extremely similar to Suda Masaki's. Even the damn good relationship between the two male leads. All Rider universes have tons of odd monsters including ghosts and especially W has a lot of the same similar angst and hot people getting in trouble and hurt and crying their eyes out. The vibe of W gets just as dark at one point even though on the whole it's funny and lighter there are still some episodes that will get to you.

W is the series after Decade so if you want to watch the Kamen Rider seasons in order then watch W after Decade.

Build comes before the 20th Heisei anniversary

W comes after the 10th Heisei anniversary

both have dual colored riders

both have an ultimate form accessed by rider fusion

detective/police plotline, one of the main villains being related to ice, the collectables being part of a museum, the strong bromance between the leads:- lupat is the perfect sentai counterpart to kamen rider w.