[Andrew Hackard]

There is no rule that says characters may not be modified in any way during combat. There are some restrictions: for instance, a person in combat may not trade Items with another player, and a Thief may not steal from a player who is currently in combat (or if the Thief is in combat herself).

However, the Scroll of Secondary Superiority cannot be played on an opponent; it says "your" Level, which means it only affects the person who plays it. So the whole argument is moot.