NES
Castlevania
Castlevania II Simon's Quest
Castlevania III Dracula's Curse

SNES
Super Castlevania IV
Dracula X

         
Alucard can transform into a Bat, a Wolf, or a Mist Cloud with some of these Relics

Relic	Effect	Location
Soul of Bat	Transform into a Bat	Long Library
Fire of Bat	Shoot Fireballs as Bat	Clock Tower
Echo of Bat	Use radar as Bat	Olrox's Quarters
Force of Echo	Attack with radar waves	Reverse Caverns
Soul of Wolf	Transform into a Wolf	Long Library
Power of Wolf	Run swiftly as Wolf	Entrance
Skill of Wolf	Special move as Wolf	Alchemy Laboratory
Form of Mist	Transform into Mist	Colosseum
Power of Mist	Extends Mist transform time	Castle Keep
Gas Cloud	Transform into poisonous cloud	Floating Catacombs
Cube of Zoe	Causes items to materialize	Entrance
Spirit Orb	Shows enemy damage	Marble Gallery
Gravity Boots	Wearer can jump high	Marble Gallery
Leap Stone	Wearer can do double jump	Castle Keep
Holy Symbol	Protection while underwater	Underground Caverns
Fairie Scroll	Displays enemy's name	Long Library
Jewel of Open	Can open locked blue doors	Bought From Librarian ($500)
Merman Statue	Summons the oarsman	Underground Caverns
Bat Card	Summons "Bat" familiar	Alchemy Laboratory
Ghost Card	Summons "Ghost" familiar	Castle Keep
Faerie Card	Summons "Faerie" familiar	Long Library
Demon Card	Summons "Demon" familiar	Abandoned Mine
Sword Card	Summons "Sword" familiar	Olrox's Quarters
Heart of Vlad	Avoid Curse	Anti-Chapel
Tooth of Vlad	STR +10	Reverse Outer Wall
Rib of Vlad	CON +10	Death Wing's Lair
Ring of Vlad	INT +10	Reverse Clock Tower
Eye of Vlad	LCK +10	Cave