When to gain winning level in combat?

[Clipper]

Originally Posted by Andrew Hackard

To clarify the last sentence: If you actually kill a monster but then have to flee the combat, you don't have to try to roll to Run Away from the monster you slew -- because it's dead -- but you don't get the rewards, either.

I think it's also important to mention that the only way you can 'actually kill' a monster without winning the combat is via some sort of automatic kill provided by a card. Such as The Mighty Germ being killed by a Halfling, an Epic Orc munching a level 1 monster or using the Potion of Halitosis to kill the Floating Nose. The original question involved beating a creature with your bonuses alone, which seems impossible to do while still having time for other monsters to enter the combat.