Glass Cannon (5e Feat)
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Prerequisites: Dexterity 13 or Strength 13 or above
Your hit point maximum decreases by 20 and you gain the following benefits to your attacks:
You gain +3 to both attack and damage rolls, your critical range increased by 1 (20 to 19 or 20, 19 or 20 to 18, 19 or 20, etc.) and when you score a critical hit, you add one additional damage die per damage type.
Before you make an attack roll, you can choose to take a -5 penalty to the attack roll. If you do so and the attack hits, it deals +10 damage of the damage type (if there is multiple, you choose one).