Grenade, Incendiary (5e Equipment)
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Martial Ranged Weapons
Incendiary grenades contain a payload of an incendiary agent, such as thermate or white phosphorous. They are typically used for destruction of enemy munitions rather than as an anti-personnel weapon.
As an action, you can throw an incendiary grenade at a point up to 60 feet away. Each creature within 20 feet of an exploding incendiary grenade must make a DC 15 Dexterity saving throw or take 5d6 fire damage and begins burning. On a successful save, a creature takes half damage and doesn't begin burning. A thrown incendiary grenade sheds bright light for 40 ft., and dim light for another 40 ft. for 1 minute.