What is your favorite moment(s) in the castlevania series?

Here are some of mine (couldn't pick just one):

SOTN: Alucard's Dream World area with the Succubus.
CV64: Carrying mandrake/mandragora through the Castle Center to blow open a cracked wall.
CV64: Encountering the first vampire in the Villa.
LoI: Discovering how the vampire killer whip is made.
CV3: Clock Tower, kill boss, discover second playable character, and have to play the stage in reverse.
CV4: Stage IV rotating room
CV2: Discovering flame whip upgrade...for free!
CV2: Discovering Dracula's mansion/tomb and carrying the body parts to revive Dracula. Dat atmosphere.
LoS2: Discovering that Alucard's sword is the Crissaegrim.

I could go on all day, so I'll stop there.

My favorite moments would have to be when you reach the inverted castle on SotN because what I thought was the end game was just the next half, the battle against Gergoth in Dawn of Sorrow, and the acquisition of every new spell, soul, weapon in the igavania games to be honest.

I liked the SotN fight with the undead 'heroes' in the reverse castle; Trevor, Grant and Sypha. But I liked the fight with Richter as well. Kind of a nice change of pace fighting a 'holy warrior against evil' for a change...

I liked the Dawn of Sorrow Alucard story. Biggest moment was fighting Soma at the end.

Castlevania: Spamming holy water on Death... (I'm a horrible person :3)

Castlevania 4: Let's make a pause here and listen this OST

Rondo of Blood : That gameplay feel so good

Symphony of the night : Soul steal ! (for the first time)

Circle of the moon: Beating the game, that was a though one

Harmony of dissonance: That Boss Rush mode <3

Aria of sorrow:
Dawn of sorrow:

Portrait of ruin : The most epic fight against Dracula AND Death !

Order of Ecclesia: Shanoa chara-design (elegant and cold)

Bloodstained : Iga is back !

Hard to pick specific moments. I like it when a one credit clear run comes together, or when I find some connection in one of the stories to real life events.

But of course Dracula making richter ponder things

Some of mine are :-

SotN - Thinking that I'd won the game and feeling elated that I'd played the best game ever but with a streak of disappointment etched in because "it finished" knowing that I'll never play a game as good for a long time. Unexpectedly, the castle then inverted and I was like "OMFG! The greatest bonus in gaming history!" Hairs. Neck. Stand.

SotN - The showdown with Galamoth. I went through the mill trying to kill this bastard. When I did eventually defeat him, I felt as though I'd travelled a thousand light years with a face like a smacked arse.

SotN - The eerie atmosphere that lingers throughout the game. Something about the mist outside the castle walls and the telescope...

CV64 - Peacefully entering and calmly strolling through a lovely garden maze ... completely unaware that a bugger of a Frankenstein wielding a chainsaw with two devil dogs were waiting for me. Peace turns to panic. Panic turns my pants to a darker shade of chocolate when I discover that Frankenstein is actually indestructible.

CV64 - Loving the noises that the female vampires made when they lunged to grab you and the sound of their heels rapidly clopping the floor as they chased you around like a chicken. Comical but creepy.

DoS - The snowy, christmas-card scenery as you make your way towards the castle. There's a sense of wonderment about it as the mysterious Yeti sneaks between the trees in the background.

DoS - Whipping and slashing enemies at The Pinnacle of the castle. The soundtrack is terrific and makes the adventure seem more epic and intense.

Sounds good to me