Ambercore Potion

This amber-colored potion uses the consumer's own vitality in its healing.

When consumed you may expend up to 2 Hit Dice. You regain Hit Points equal to the roll plus your constitution modifier, you also gain temporary Hit Points equal to that of the total.

If the Temporary Hit Points still remain after a number of minutes equal to your Constitution Modifier they become toxic. You suffer necrotic damage equal to the remaining amount, and gain a point of exhaustion. You can't be killed outright by this damage, only knocked unconscious. This Damage can only be mitigated by Immunity.