The action adventure game "Castlevania: Symphony of the Night" (C:SofN) was released in October, 1997 by publisher and developer Konami. The Castlevania series is well known for quality graphics and gameplay, and superior level design. Sacrificing graphics for a retro-2D look and classic Castlevania ambiance, Konami brought the traditional game experience to the next-gen consoles of the time. (See references 1) Alucard, the protagonist in C:SotN has the ability to shapeshift. "Soul of Wolf" allows him to access his wolf form.
Travel to the Alchemy Laboratory to pick up the "Skill of Wolf" and then to the Outer Wall for the "Soul of Wolf." These are required to do a special attack while in wolf form.
Press the "Wolf" button on your controller to transform into a wolf once you obtain the "Soul of Wolf."
Perform a "Wolf Charge" attack by pressing the directional pad on the controller in a down to forward motion. Start by holding down and circle counterclockwise to the forward position and then press the attack button.
"Castlevania: Symphony of the Night" is a multi-platform game, so the button you press to transform into a wolf will depend on the system and controller you are using. Check your game manual if you are not sure.