You, and perhaps only you, have the ability to prevent global annihilation in the video game Demon Killer. Stop the demon invasion by stocking up on a wide variety of weaponry. Don't stop improving and expanding your photographic horizons. If you want to stop the demons from getting in, you'll need a wide variety of weaponry. Take the money and run from the monsters! There is a need to strengthen your weapons and stock up on ammunition, both of which may be accomplished by upgrading them. Headers are particularly damaging to the opponent. Do you have what it takes to withstand Satan's assaults?
Take gold from devils. From the main menu, you can make purchases of ammunition and powerups. If you aim for the head, you'll do more harm.