Tiamat's Gift

Tiamat's fiendish blood runs strong in you, unlocking a resilience akin to the dragon queen herself. You gain the following benefits:

• Increase your Constitution score by 1, to a maximum of 20.
• You have resistance to cold damage, poison damage, lightning damage, and acid damage.
• You have advantage on saving throws against being poisoned.
• You may change the damage type of hellish rebuke from fire to cold, poison, lightning, or acid.