If you have a heavy weapon like a great sword, slow attacks can be a problem. To hit an enemy twice quickly, stand very close to them and attack. Then just as it connects, press L to dash backwards. As soon as it stops, you can attack again; if you are still close enough it should hit. This is quicker than just attacking twice normally.
Bad ending
Use the Paranoia Soul to enter the mirror during the second battle with Dario Bossi. Defeat Aguni, then return to the other side of the mirror and get the Magic Seal. Then, go to the center of the castle and enter the Boss door without Mina's Talisman.
Best ending
Use the Paranoia Soul to fight Aguni. Collect the Magic Seal, then return to the center of the castle. Have Mina's Talisman equipped when you enter the Boss door, then successfully complete the game.
Chaos Ring
Get 100% of the Souls to get the Chaos Ring, in the abyss.
Completion bonuses
Successfully complete the game with the best ending to unlock Boss Rush mode, Sound Test mode, and New Game +. Successfully complete the game with Soma on the hard difficulty setting to get the Hell Flame Soul (triple fireball) move.
Death Robe
Finish Boss Rush mode in less than six minutes to get the "Death Robe". It a powerful armor, but Dracula's Tunic is better.
Defeating Dmitri
If you have a Witch Soul, let Dmitri copy it. The projectile attack from this Soul is fairly easy to avoid and will make this fight much easier.
Defeating the Iron Golem
Use the Imp Soul; it switches HP damage to MP damage.
Easier Boss Rush mode
Activate the Devil Soul and use the Valmanway Sword. You can take down all the Bosses in less than five minutes.
Easy Soul Eater Ring and money
Get the Mimic Soul and go to the Clock Tower. There is a save room with a spike pit next to it at the bottom right corner of the Clock Tower. The Mimic Soul will usually give you 500 gold each time you are hit by the spikes. Whenever you get low on health, go to the save room, heal, and repeat.
Get to Bosses early
Get a Chaos Ring, a sword like the Alucard sword or a dagger-like weapon (must teleport Soma like the Alucard sword), the Succubus Soul, Treant Soul, and anything else to improve magic restoration. Go to a door you need a soul and use the Succubus Soul. Before you finish, use the dagger weapon. Note: For some doors you must be farther away so the door does not lock you out, stating that you need a seal. You should know be in the Boss room. Note: Do not use this trick on walls that have rooms next to them. Also, for Demetri's first fight in the Garden Of Madness, if you enter the door from the right, Demetri's scene happens and Somacan still move. Press A to read through dialogue; you will not be able to skip it. This trick can be used to go through places, such as the barriers in maze of the numbered rooms. It is possible to go through the game in nearly any order.
Gold Ring
In the left part of Subterranean Hell, there is a slot machine door. If the last three digits of your gold are 666, the door will slide back, and you can get the Gold Ring. With the Gold Ring, you can get more money from enemies and candles.
Julius mode
Equip the Paranoia soul and without Mina's charm equipped, enter the mirror to fight Dario's inner demon.
Last two abilities
The final two abilities are enemy Souls. These Souls are the Procel and Mudman. The Procel is found in Subterranean Hell and Mudman is found in the Abyss. These Souls allow you to walk through water and stand freely.
Leave level boundary
This trick requires the Succubus Soul and the Cutall weapon. Go to the last save location in the Abyss and do the special attack on the very end of the wall, not near the door Keep doing the special move until you fall out of the level. You can get back to the save room. If you have a 100% map completion, you will uncover about 56% more if you manage to get back in the save room. Note: If this is done, you will make the final Boss impossible to defeat. After you defeat him, he will just respawn.
Nunchakus
Finish Boss Rush mode in less than seven minutes to get the "Nunchakus" weapon.
Play as Alucard in Boss Rush mode
Successfully complete the game with Soma with a 100% completion and complete Julius mode. Then at the Konami logo, press Up(2), Down(2), Left, Right, Left, Right, B, A. Remain idle until the Konami logo appears again, then press Up, Down, then hold Up until the sound of a door opening is heard. Select Boss Rush mode to play as Alucard with his Alucard Set.
Rare Ring
Have the Game Boy Advance game Castlevania: Aria Of Sorrow in the cartridge slot and start a new game to have the Rare Ring in your inventory.
Rocket Launcher
Finish Boss Rush mode in less than five minutes to get the Rocket Launcher "RPG".
Secret monsters
There are three secret monsters (Yeti, Mothman, and Flying Humanoid). To get the Yeti, you must first get the Waiter Skeleton Soul then go back to the very beginning of the game. You will see him walking in the background. Toss the curry and he will come up where you can attack him and gain his Soul. You will need the Rycuda Soul leveled up to at least two to get Mothman. Go to The Pinnacle to the area where there are two final guards and a light in between them. Strike the generator next to the light with Rycuda and Mothman will appear. For the Flying Humanoid, you will need the Mandragora Soul. Enter the room in between the Zephyr Boss room and a save room, then use the Soul.
Semi-immortal Succubus
Equip the Bullet-type soul Succubus and a back-stabbing weapon (for example, Cinquedia). Press Up + Y to activate Succubus. Just as Soma raises his arms, press A for a special attack. Soma will thrust forward and back, and will be surrounded by a red aura. That aura only lasts about three seconds -- work as fast as possible. Walk into an opponent and stay in his space until the aura dissipates. Three things will happen when the aura disappears: The enemy will take damage based on your INT level (but normally around 200-300 damage); you will regenerate health (just like using Succubus normally); and you can walk through enemies with taking damage (like Iron Golem, Valkyrie, etc., minus the constant MP cost). This is sometimes extremely difficult to do, but once mastered the results are amazing. This glitch has two major flaws. You can only move sideways, with no jumping, sliding, back-dashing, "Hippogryphing", or using Souls (except Black Panther). Also, the chance of doing damage is random. Sometimes damage is done instantly, and sometimes not at all.
Soma continually jumps
In the Mines of Judgment is a room that has a Bugbear, a Slogra, and a small ledge overlooking the room. Equip the Enchant-type soul Draghinazzo (stops flinching after taking damage) and destroy the Bugbear. Destroying Slogra is optional. Press R to activate Guardian-type soul Bat Company and fly into the ledge, just barely on the edge. Deactivate and Soma will be crouching on the ledge. Slide twice in the direction you are facing. Once you fall off, keep pressing B to jump repeatedly. This may take a few attempts, but Soma will continually jump until he touches the ground.
Soul Synthesis warning
If you want the best weapons in the game, you must give up some of your Boss Souls. For example, if you want the Claimh Solais, then you must give up the Gergoth Soul.
Terror Bear
Finish Boss Rush mode in less than eight minutes to get the "Terror Bear" weapon.