The Retropulse is a glitched item which could be acquired prior to patch 1.5.1 in Galaxy on Fire 2 . It had no description and was rarely offered in the space lounge. The item was likely a beta item which was left in the game by accident. When used, a pink bra is dispensed out of the ship followed by the repeating sound of a tractor beam. After a while, it disappears with no effect on the game. If you purchase the Valkyrie DLC (or update to version 1.5.1), any Retropulses you own will turn into AMR Sabers.