Shadowhunters don't use guns or grenades because their marks prevent the gunpowder from igniting. They need to apply runes to their weapons to damage demons. They will immediately heal otherwise. Demons can only be permanently harmed by Seraph Blades, which are made by the Iron Sisters from adamas. Seraph Blades can only be activated by a Shadowhunter by naming it after an angel, but never Raziel. For werewolves, the best weapon to use would be one of pure silver or a Seraph Blade. For vampires, holy water and seraph blades can be used. If unprepared, wooden objects make good weapons and forcing them into sunlight will be very effective. For fey, pure iron should be used or Seraph Blades. When going anywhere, make sure to have Seraph Blades, extra knives, a stele, and a long range weapon such as a bow.
"Black for hunting through the night, For death and morning the colors white, Gold for a bride's wedding gown, Red to call an enchantment down, White silk for when our bodies burn, Blue banners when the lost return, Flame for a newborn Nephilim, And to wash away our sins, Gray for knowledge best untold, Bone for those who don't grow old, Saffron lights the victory march, Green will mend our broken hearts, Silver for the demon towers, And bronze to summon wicked powers." -Shadowhunter nursery rhyme.
"Black for hunting through the night,
For death and morning the colors white,
Gold for a bride's wedding gown,
Red to call an enchantment down,
White silk for when our bodies burn,
Blue banners when the lost return,
Flame for a newborn Nephilim,
And to wash away our sins,
Gray for knowledge best untold,
Bone for those who don't grow old,
Saffron lights the victory march,
Green will mend our broken hearts,
Silver for the demon towers,
And bronze to summon wicked powers."
-Shadowhunter nursery rhyme.