Here we have an interesting instance of a recurring theme but no apparent structure by which to measure it. Though, we can easily see the congruities: In Akumajo Dracula X68000, Simon will exit the confines of stage six, the clock tower, and shortly thereafter find himself in a surprisingly animated hall of mirrors before battling an obvious boss creature; armored foes and the mirrors, themselves, will impede his progress. Within Rondo of Blood's seventh stage, Richter will exit the gear-filled area of the clock tower to find himself in the afore-chronicled sword-lord-filled hallway; before its pendulum room and the following boss habitat, Richter will come to a hall of mirrors where his progress will be impeded by armored foes and a minor enemy forecast by a twisted reflection. Juste Belmont, too, encounters this phenomenon in the transient Sky Walkway, an area in direct proximity to Harmony's clock tower; here, he'll find as his main obstacle a twisted reflection, itself an armored foe. Finally, in Aria of Sorrow, Soma Cruz locates possibly the same hall in the Inner Quarters (positioned on the map in a convincing location compared to Rondo and X68000's like areas), where he'll be stifled by a twisted reflection and--yep--armored foes. (Suggested by Kev.)

In Symphony of the Night, Alucard has one final in-game meeting with Maria Renard in the the Marble Gallery, in a ceremonial-type room (the castle's dead center, specifically) hidden beneath its giant clock. After Alucard equips the gold and silver rings, the clock room's brickwork will be forced open, and it'll make way down to a lift that will carry him to this meeting room. In Harmony of Dissonance, which is prequel yet still derivative of this design, Juste Belmont will while on the Castle Top Floor drop down to discover the same lift.

In both cases, the lift will transport the hero down into a claustrophobic cavern that houses a cubicle-type room whose outside must be traveled around to enter the room from its bottom. The designs are all too similar: The room's outside corners are carved off to present a smooth triangular stop, and its texture is an alternating pattern of vertigo-sacred eye. At the bottom of the cavern, the heroes can enter the actual meeting room by slipping through a convenient opening. Alucard will have a meeting with Maria, as mentioned, and Juste will have perhaps a final encounter with Maxim Kischine.

The meeting room has a very centric design, as if its centerpiece holds hostage an essence of sorts. The described experience isn't limited; in both cases, the hero will see this room again in another form: Alucard will find its reverse cousin via the upside-down castle, and Juste will find its replica in the second, "transient" castle. It should be noted that Juste can only enter this replica by breaking a seal (as Alucard had to do using the rings) on the Castle Top Floor by harnessing the collected body parts of Count Dracula. Also, to further link the KCET products, Juste, too, can equip goods of his own, two friendship bracelets, to placate a friend and to solve a mystery. (Suggested by Kev.)

Alucard's path in Symphony of the Night's Underground Cavern will see his arrival atop its impressive and intimidating waterfall. Since he will be without power sufficient enough to clear any horizontal gaps, he'll have to drop down into the chasm and endure its long drop. In Aria of Sorrow, a game clearly modeled directly after Symphony, Soma will within the castle's Underground Reservoir arrive at the very same waterfall but not from the same entrance; rather, Soma will have worked his way around from the area's left side. The real estate between the fall's top and the top-right exit is blocked off by a pillar.

Since the distance between the waterfall's top and the exceedingly-tall-room's top-left exit is considerable, Alucard will have to take a leap of fate and dive into the aforementioned chasm, the flowing water rushing its way to the shallow pool below. Soma will upon reaching the waterfall's top already have the means to clear said distance.

The obvious and safest path forward is the room's bottom-left exit, but a point of interest lay to the right. That is, both heroes' paths will be blocked off at the fall's impact point, which creates a force great enough to prevent its breach. Alucard can return later with a snorkel-type item and tread the rough water and its glowing haze, while Soma will need a little help from transforming-type tactical souls.

But most curious still is what lay beyond the room placed directly to the waterfall's left. Both of our Dracula-like heroes will find the answer after discovering respective items that will afford them bat power, using which they can scale back up the long chasm, enter the room in question, and snag a new weapon for their destructive pleasures. (Suggested by Kev.)

Recurrence in Castlevania, we find, is not merely limited to castle structure but to idea, which is the case when dealing with "Time Stoppers." Battling foes in clock towers isn't something new--it's been a series staple from the start; modern series offerings, however, have supplied a theme to atop-the-clock-tower battles, as heroes must engage foes who utilize time, itself, as a weapon. Aria of Sorrow and Portrait of Ruin feature Death, whose association with time-passing and death is obvious. Dawn of Sorrow's Cursed Clock Tower houses Zephyr, who has a noted time-stopping ability. And Curse of Darkness' Eonemaos Clock Tower pits you against St. Germain, a master of time who also has the ability to halt its flow. (Suggested by Kev.)