Kabuki Den is my favorite Tengai Makyou game and certainly ranks as one of the upper-echelon PC Engine RPGs. Contrary to chronology it may be, but I always recommend playing KD first if you're interested in the PCE TM games. While Ziria initially seems primitive and slow and even Manji Maru needs a few hours to really hit its stride, Kabuki Den is crazy, colorful fun from the outset and is sure to pull you in with its vibrant visuals, uproarious cinemas, and wacky main character.
Of course, none of the showtime stuff would mean much if the actual gaming elements didn't hold up their end of the deal; thankfully, Kabuki Den's in-game mechanics and superficials are perfectly fine. Battles are reminiscent of old Final Fantasy rumbles presentation-wise. Characters and monsters run back and forth to hit each other, and spell animations are tossed in, but the scuffles play out fairly quickly, and you get some nice (if simplistic) backdrops to boot. There's even a command that allows you to engage in battle whenever you so desire, so you don't need to run around in circles waiting to be attacked if you want to level up.