Sapper (5e Feat)
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Prerequisites: Proficiency in alchemist's supplies
You have developed a way to create small bombs that are an effective means of combat. You are proficient with the bombs, which are simple ranged weapons that weigh 1/2 pound and have the thrown and finesse property with a range of 20/60. On a hit, the bomb deals 2d4 fire damage. Hit or miss, each creature within 5 feet of the target, including the target, must succeed on a Dexterity saving throw or take 2d4 piercing damage from the shrapnel. The DC for the saving throw equals 8 + your Intelligence modifier + your proficiency bonus. If you take fire damage while you are carrying bombs, you must make a Dexterity saving throw (DC = damage taken), or all the bombs in your possession will detonate as if each one successfully hit you and you failed each saving throw (though others within range must still make theirs).
For every 1/2 hour of work with alchemist's supplies and reagents commonly found in most markets for 10 gp you may make an Intelligence check using your tool proficiency against a DC of 12. Each successful check creates 1d3 + 1 (also known as 1d4, reroll 1s) bombs.