Curse of Monstrous Shape

You create a cursed artefact with the power to force a target humanoid to take on a monstrous shape for the span of 10 years. Breaking the curse requires the target to perform a specified feat before the curse expires. Casting the spell requires three specialised components: a non-magical item to which the curse is bound; the intended target’s true name; and a specified manner in which the curse may be broken.

The item must be huge or smaller. It may be something naturally occurring, and it can be a plant. It may not be a living creature, but it may be an article composed of such materials, such as an ivory ring or even a shrunken head. While the item you choose may feasibly be anything from a tiny dandelion to a huge statue, it must have some significance to either you or the intended target, and should have some relationship to the way the curse may be broken. A few examples are listed in the table below. The item you bind the spell to becomes a cursed artefact, and is magically preserved for the duration of the curse, except for signs of decay that mark the countdown for the curse’s duration, as detailed under Breaking the Curse below.

If the chosen item does not already have an AC and hit points, its AC becomes 5, and it gains a number of hit points based on its size: 10 Hp for a tiny or small item; 20 Hp for a medium or large item; 30 Hp for an item larger than this. Regardless of what form it takes, the artefact has resistance to all non-magical damage, and all magical damage from spells of 8 level or lower. It is also immune to magical effects that would cause it to change form. If it is destroyed early, the creature cursed by it also dies, except where destroying the artefact is required to break the curse.

To trigger the spell, you must be holding the cursed artefact, and be within 60 feet and in line of sight of the intended target. You must speak the target’s true name followed by a pronouncement of how to break the curse. The target creature hears your words in their mind in a language they understand, even if they cannot hear your words directly. In addition, they have an instinctive knowledge of the time remaining for the curse, the manner in which it may be broken, and the consequences of failure or for allowing the artefact to be damaged.

Once the curse is triggered, the target creature immediately gains 4 levels of exhaustion, develops bestial aspects, and its stat block changes in the following ways:

• The cursed creature grows one size larger;
• It is considered a monstrosity;
• Its Strength and Constitution scores each increase by 2d4 + 2, as does the maximum for each score.
• It gains natural armour equal to 13 + its Dexterity modifier, and loses any armour proficiencies. Any armour it's wearing when the curse is triggered is destroyed.
• The cursed creature no longer ages and is immune to magical aging effects.
• The creature cannot change its shape in any way, and is immune to magical effects that would cause it to do so.

Breaking the Curse. The cursed artefact acts as the spell’s timer, decaying, weathering or dying slowly over the course of ten years. At the conclusion of the period, the artefact is magically destroyed and the curse ends. Your alignment at the time you created the cursed artefact determines what happens to the target when this occurs (If your party does not use the rules for PC alignment, you and the DM should decide together what the most likely outcome should be based on your character’s decisions up to that point; the DM has final say).

Good. The cursed creature returns to their true form with 4 levels of exhaustion.
Neutral. The creature remains in their altered shape and cannot be returned to their original form by any means short of a wish spell. They retain all the curse’s alterations to their stat block with the exception that they now age and are no longer immune to magical aging effects.
Evil. The creature dies, retaining their monstrous form.

If the cursed creature can perform the necessary feat specified when triggering the curse, the curse is lifted, and the creature returns to its true form and is considered to have just finished a long rest.

A remove curse or dispel magic spell cast upon the creature has no effect. Anyone attempting to cast these spells recognises this before the spell slot is consumed, but after their action is used. Successfully casting dispel magic or [spell]remove curse[/curse] upon the artefact forces the cursed creature to make a Charisma saving throw against your spell save DC. The creature has disadvantage on the save if it is further than 60 ft. from the artefact or out of line of sight. If the saving throw fails, the artefact suffers 1d4 damage. Breaking the curse in this way requires the spell to be cast at least three times, with a successful saving throw on each. These successes need not be consecutive.

Ritual Variant. Preparing the spell as a ritual changes the way the spell is cast in several ways. You may perform the ritual and create the cursed artefact away from the intended target. The curse does not take effect until you meet the requirements for triggering the curse as mentioned above, however, casting the spell as a ritual gives you the option of including additional material components that affect the way the curse shapes the target creature’s monstrous form. The table below offers example ingredients and the effect they contribute. Any feature that is not given a corresponding component is considered to be the default shape the curse will cause. If you include multiple ingredients for one section (ie. A bird’s eye and a snake’s fang both affect the form’s head), the new form will incorporate aspects from both choices where possible, or from the first ingredient you added where this amalgamation is not possible. The table does not consider every possible outcome and the DM may decide that other ingredients generate different forms, such as a fly causing the target to manifest compound eyes, or a strip of elephant hide causing it to grow a prehensile trunk.

Most aspects grant the cursed creature additional abilities or traits. If you are using ingredients and aspects unspecified by the table, the DM decides what - if any - additional traits each imparts.