Create a knight, and train him to level 40 with a high fire mastery. Fire 
mastery can be increased by getting some special items, such as Rune Items. Make 
sure you can hold at least 48 Fire Mana. Capure a Fire Elemental, and research 
the spell "Fire Siphon". The spell Chivalry is also required. You can learn it 
at level 40. Select those two spells so that you can cast them. Start a battle, 
and check the resistance of your enemy. It is best if their resistance is 0%. 
First, cast Chivalry. It will remove effects such as Poison and will raise you 
and your enemy's mana to the maximum. In your next turn, cast Fire Siphon. This 
will drain your enemy's red mana and add it to your life points (not your 
maximum life points).