Familiars
Fairy

The Fairy Familiar will help you out of tight situations - if you're low on health or turned to stone, she'll heal you - providing you have Hammers or Life Apples in your inventory. She will also point out breakable walls. There was also a counterpart to this in the Japanese, the Sprite familiar, who did the same thing, but would sing under the right conditions.

Sword

The Sword Familiar is probably the most all-around powerful - the higher its level, the more aggressive it will be. Once it hits level 50, you can wield it as a sword, although it does not gain experience in this form. At level 99, it has the highest attack power of any weapon in the game. You also have access to the Sword Brother's spell, which will summon a gigantic sword that will hover in the middle of the screen and then send out a powerful blast, harming everything in the vinicinity. Rather powerful and useful for those times in the inverted castle were you are absoultely overwhelmed.
(MP 30) D, DF, F, UF, U (Hold for 2 Sec.), D + Square or Circle

Bat

The bat will fly by your side and attack enemies - not too useful by itself, but when Alucard changes into bat form, they'll summon a flock of them. Much like the options in Gradius, they'll follow your movement and attacks when you attack. The higher the level, the more that are summoned.

Ghost

The ghost will eventually power up to suck away enemy life, much like Alucard's Soul Steal power.

Demon

The demon is an average attacker - however, you'll need him to open a few hidden passages. This familiar also had another counterpart in the Japanese version that was a parody of a famous voice actor, but served the same function.

One Time Use Weapons

There are quite a few single-use throwing weapons found throughout the game. Unfortunately, since their use is limited and they're awkward to equip, you probably won't use them very much. On the top row are the Neutron Bomb and Iron Ball weapons. In the middle row are the Magic Missile weapons (which summons a magical bow) and the shuriken-like Buffalo Stars. On the bottom row are the TNT weapons and the "Power of Sire", which will call on Vlad Tepes to administer punishment to everything on the screen.

Spells

Dark Metamorphosis

A pretty darn handy spell to know for the beginning of the game. When cast, Alucard will turn red for a short amount of time. During this period, any enemy that sheds blood when you hurt or kill them will heal you (much like actually drinking blood.)
(MP 10) B, UB, U, UF, F + Square or Circle

Hellfire

Every true Castlevania fan is wary of Dracula's main attack...transporting, opening his cape and sending three fireballs out. Hellfire is exactly that. Alucard will mimic his father's actions almost precisely. The time it takes to execute and its power make this spell usefulness questionable. If you do a half circle rather than a quarter circle, you'll shoot those large black fireballs that Dracula attacks with.
(MP 15) U, D, DF, F + Square or Circle

Soul Steal

This spells will send out a few spirits that will actually take life away from enemies and give it to Alucard. Takes the most magic power of any spell, but very useful in various situations.
(MP 50) B, F, DF, D, DB, B, F + Square or Circle

Summon Spirit

One of the simpler spells, Alucard will call out a single spirit that will track down an enemy on the screen and hit it a few times before disappearing.
(MP 5) B, F, D, U + Square or Triangle

Tetra Spirit

Much like a Summon Spirit spell times four. Four spirits will be summoned to fly around the screen and wreak havoc. Much more useful than the normal Summon Spirit attack.
(MP 20) U (Hold for 2 Sec.), UF, F, DF, D + Square or Circle

Wing Smash (as Bat)

You often see Alucard's second Doppelganger using this attack. Turn into a bat and execute this manuever, and Alucard will charge forward very fast, causing damage to anything in its path. Great for flying enemies, especially since the bat form's fireballs aren't that powerful.
(MP 8) Hold X, U, UB, B, DB, D, DF, F, Release X

Wolf Charge (as Wolf)

I pretty much still regard the wolf as almost useless, but this attack will at least give some purposde to the beast. It is very similar to the Wing Smash, only obviously the wolf is on the ground; he will charge the enemy quickly and inflict a good amount of damage.
(MP 10) D, DF, F + Square or Circle

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