Magna-Medicinal is the greatest form of healing one can perform, able to bring almost any creature back to life by sacrificing the very flesh of a devout follower of Sylvian, to Sylvian.
When performing Magna-Medicinal, the user has a choice between exchanging an arm or a leg for a life.
If an arm is chosen, the user will no longer be able to wield 2-handed weapons or otherwise perform actions that require more than one arm.
If a leg is chosen, the user will be forced into the prone condition and will be unable to get up without the support of an object/person. Otherwise, they are forced to crawl until a prosthetic/cane can be obtained.
This feat must be performed using an action, and requires organic flesh directly from the user in order to work properly. If attempting to use a prosthetic in place of a limb, it will simply cause the healing target to become dead permanently as punishment for attempting to scam Her Lady Sylvian.
Upon performing this feat, make a Constitution saving throw (DC 15). On success, the patient comes back to life and the user takes 1d6 slashing damage from blood loss. On failure, the user will simply become unconscious as soon as the procedure is finished, however the healing target is guaranteed to come back to life regardless of a success or failure.
When successfully performed, the healing target will come back to life with 4d4 + 4 health and be cured of any and all status effects, as long as it wasn't something they were born with (poison, addiction, exhaustion, etc).