For infinate lives in this game, use the DOS utility DEBUG.
 First backup your game to be edited, then type the following
 from the dos prompt:   ([EGA] game cheat only!)

 ren e:\towerega.exe cheater.cht
 debug e:\cheater.cht
 e 7e5 90 90
 w
 q

 Then rename CHEATER.CHT back to its previous name.