Electron Pack
Combo A
Proton Backpack
Proton BackpackEffect
If the player also has 
Zombie Bullets or 
Ghost Bullets , kills with the Proton Backpack spawn 
Gunslinger's Ashes ghosts that attack enemies.
Proton BackpackIf the player also has Zombie Bullets or Ghost Bullets , kills with the Proton Backpack spawn Gunslinger's Ashes ghosts that attack enemies.