Choose one creature that you can see within range. You transform the creature into a different creature of equal or less CR/Level. The transformation takes a month to complete and lasts for a year, or until the target drops to 0 hit points or dies. If you concentrate on this spell for the full duration, the transformation becomes permanent.
An unwilling creature can make a Wisdom saving throw, and if it succeeds, it isn’t affected by this spell. The target’s game statistics, including mental ability scores, are replaced by the statistics of the new form.

It retains its alignment and personality.

The target assumes the hit points of its new form, and when it reverts to its normal form, the creature returns to the number of hit points it had before it transformed.

If it reverts as a result of dropping to 0 hit points, any excess damage carries over to its normal form.

As long as the excess damage doesn’t reduce the creature’s normal form to 0 hit points, it isn’t knocked unconscious.

The creature is limited in the actions it can perform by the nature of its new form, and it can’t speak, cast spells, or take any other action that requires hands or speech unless its new form is capable of such actions.

The target’s gear melds into the new form.

The creature can’t activate, use, wield, or otherwise benefit from any of its equipment.

Shapechangers aren’t affected by this spell. This spell can’t affect a target that has 0 hit points.