Things You'll Need
Instructions
Deploy a unit containing a wizard unit or upgrade a unit to become a wizard. The basic fighter unit with a charisma score of 50 or higher who is also at least fourth level can be upgraded to a wizard. Remember to keep your wizards in the back row so that they deal the most damage with their magic attacks.
Keep the wizard's alignment as high as possible. To become a lich, a wizard must go through several upgrades, one of which requires that the unit's alignment must not be too low.
Upgrade the wizard to the mage class. This class requires the wizard to be at least level 10 and have an alignment of at least 10. The mage class is very similar to the wizard, except the unit now has an area attack that affects all enemy units.
Turn your mage unit into a sorcerer. The sorcerer class doesn't have any level or statistical requirements, you just have to use an undead staff item on a mage unit. Sorcerer's are very similar to the mage unit except they get an additional attack during every combat.
Find an undead staff to use your mage. These are sometimes found randomly after battles or can be hidden in certain levels. A sure way to get an undead staff is to return to Diaspola after defeating the enemy boss there and locating the mage Borgnine. He will trade demon statues for an undead staff. There are several locations where demon statues can be recovered. On this same level a demon statue can be found by taking the item received from the hidden Roshafallion temple to the city Somyul.
Make the final upgrade from sorcerer to lich by using an undead ring on the sorcerer unit. Like the undead staff item, they can occasionally be found randomly. Otherwise you can trade for one by getting the "lexicon" item in Muspelm and then giving it to the wizard Badista in Sharom, who will reward you with an undead ring. The lich is the most powerful spell casting unit, using three separate magic attacks per combat.