A trap that give us resources while rearming the trap !!

The trap's main essence is that it KOs the troops that comes near it [ splash ] [ air or land]

Then it needs to be rearmed : while rearming , you can get 10% to 50% of the resources that were used to make the troop.
Example : Barbarian = 160x10% = 16 Elixir
Dragon = 25000 x 10% = 2500 Elixir
Golem = 350x10 = 35 DE

On upgrading , more % of the kill can be retrieved !!

< UNDER CONSTRUCTION , PLZ BEAR >

I think you need to come up with a trap which would make sense to have this special ability, because it wouldn't make any sense for a normal trap to have it. Also, I think that with the addition of such a trap, people will start to suggest that all the traps have this effect when killing an attacking troop, so I personally don't think we need this.