Helpers running away

[Clipper]

I think you might be referring to cards that allow one or two players to escape automatically. These do not allow you to escape a combat which is in progress, but simply mean that if the combat owner agrees he can't win the combat and is forced to declare loss and Run Away, then the munchkins escape the monsters without rolling. Such cards have no effect on a combat that is in progress.

There are cards that can let a helper leave a combat before it is over (in this case they don't Run Away at all), and in that case you can get a new helper unless the card that allowed the helper to leave said otherwise.

If somebody does play one of the few cards that forces you to lose a combat and Run Away (e.g., Potion of Cowardice), then it is no longer during combat, so you can't play most of the cards that would remove monsters. Only cards like Magic Lamp that say they can be played while Running Away could remove monsters at that point. Neither Friendly nor Dead would be allowed.