School of Transmogrification
Wizard Subclass (Source: Player's Handbook)
This is a variant of the School of Transmutation subclass, replacing it for use in this setting. It is as follows:
The School of Transmogrification teaches transmutation generally, but with a particular focus on a subset of such magics that alter the form or physiology of living creatures to improve or extend function. A common preference among Transmogrifiers to overcome obstacles via the expedient of simply enhancing however many creatures in whatever ways are necessary to render the obstacle trivial predisposes them to wanting companions to experiment on...er...uh...enhance with their spells. Thus, they tend to fit into adventuring parties easily and well.
Transmutation Specialist
Beginning at 2nd level, you are specialized in spells belonging to the transmutation school of magic. Each time you gain a wizard level (including the level when you gain this feature) you can add two wizard spells of your choice of any school of magic to your spellbook as normal, and you may also add one additional wizard spell from the transmutation school to your spellbook. All of these spells must be of a level for which you have spell slots, as shown on the Wizard table.
Transmogrifying Mastery
As you progress in this class, you will master specific spells (detailed below) that alter the biology, physiology, or form of living creatures. The spells you master due to this feature are always considered to be prepared by you, and do not count against the number of spells you can prepare each day.
You can cast a spell you've mastered from this feature at its lowest level without expending a spell slot, if the target of the spell is a living humanoid creature. You can do this a number of times equal to your Intelligence bonus (minimum 1), and you regain all expended uses after completing a long rest. A spell cast in this way has a duration of 1d4 hours instead of its normal duration, and its effects on a target can be ended early as a bonus action by you or by the target.
Rudimentary Transmogrification: At 2nd level, you master Feather Weight, Jump, and Longstrider. You add these spells to your spellbook, if they are not there already.
The target of Jump and Longstrider as cast by you takes on minor cosmetic changes for the duration of the spell. Their legs are noticeably longer, more muscular, or perhaps even bestial as you prefer.
Basic Transmogrification: At 6th level, you master Enhance Ability, Alter Size, and Spider Climb. You add these spells to your spellbook, if they are not there already.
The target of Enhance Ability cast by you takes on minor cosmetic changes for the duration of the spell corresponding to the effect chosen, such as bear-like changes for Bear’s Endurance or cat-like changes for Cat's Grace. The target of Spider Climb cast by you takes on minor cosmetic changes for the duration of the spell that are suggestive of a spider.
Intermediate Transmogrification: At 10th level, you master Feral Form, Quickened Form, and Rocky Form. You add these spells to your spellbook, if they are not there already.
Advanced Transmogrification: At 14th level, you master Tenser's Transformation, and add it to your spellbook if it is not there already. Additionally, you may cast Tenser's Transformation on yourself or on a living humanoid creature within 60 feet that is visible to you and willing. If you cast Tenser's Transformation on another creature, all instances of "you" and "yourself" in the spell's description are understood to refer to the target of the spell rather than you. The target of Tenser's Transformation cast by you becomes visibly more muscular and physically powerful for the duration of the spell.
Regenerative Transmogrification
At 14th level, you add the spell Regenerate to your spellbook. It is a wizard spell for you, and you do not need to provide material components to cast it. When cast by you, this spell causes the skin and flesh of the target to take on a greyish green hue and to become tough and rubbery for the duration of the spell.