After getting to the Spell Shop (the one that the Monk leads you to), buy Attack +50 Potions. Go to the Sha'armet Tournament and use one. Note that You may want to save the game before doing this. Go into a fight and lose on any round. You can also win, but you cannot get it full if you do so. After losing, check your stats. Some of your attack should still be up. Note - Do not try this with Dodge Potions, as it will take your Dodge down.
Shoot all the crystals that connect him to the computer. He will then be free and walk around the room, attacking you. He has three basic attacks. The deadliest attack is when he jumps high in the air and crashes on your head. Avoid this attack when possible by running away when you see him jumping up. He is invulnerable to your attacks. The only way to defeat him is by shooting an oval spot on his back, between his shoulders. Try getting behind him and shoot that spot continuously. The best way to do it is to spin around him. If you can do it quicker than him, he might turn his back to you occasionally. Use this opportunity to fire at the spot.
The following is a list of spells and a brief description:
SPELL - DESCRIPTION Truth Spell - Forces a liar to say what he or she knows. Mix a Wiki and a Dead Man's Tongue in a Beshe'm. Love Spell - Makes a woman fall in love with you. Mix two Sham Testicles and nine Mouse Teeth in a Beshe'm. Invulnerability Spell - For temporary invulnerability. Mix a Virgin's Blood and a Tear or Ether in a Beshe'm. Unmask a Demon Spell - Forces a demon with a human appearance to reveal his demon form. Mix a Sham Horn and Dew Of Light in a Beshe'm.