Salvaging

You may Salvage any unit and recoup 25% of the Storm Power you spent to build it.

If the unit has been damaged, you will recoup less Storm Power. For example, if you build a unit for 400 you can Salvage it for 100. However, if one third of its hit points are gone, you'll only get 66.

One last thing to know: If the damage goes beyond half of the unit's hit points you will recoup no Storm Power at all.