Boon of the Biomancer (5e Epic Boon)
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Boon of the Biomancer
You combined your mastery of shapeshifting with knowledge of biology to fully understand your capabilities.
When you use any spell, ability, feature or effect (The Boon will refer to all of these as spell for brevity) that transforms you into a different creature, you can transform into a creature up to 2 CR higher than what you otherwise could. For example, a level 20 character using Shapechange can become a creature up to CR 20 without this boon, but CR 22 with it. You can also cause an effect that would transform you to fail without making a save against it (Except against deities) if you don't wish to be transformed. Additionally, you are immune to disease and poison, and can control if it has an effect on you or not, including what effects it has. You can do the same with curses that affect your biology, such as Vampirism and Lycanthropy. For example, you can use a Lycanthrope form and statistics as if you've embraced the curse, but avoid the change in alignment that comes with it. Any such disease or curse that alters your creature type cannot be used in any way without changing your creature type, you have no control over that. You can't be a vampire without being undead, obviously. If you decide not to use an affliction in any way, you don't contract it as if you were immune. You cannot carry a curse or disease without using it in some way.