True Polymorph

Choose a creature or nonmagical object that you can see within range of the spell. You transform the creature into a different creature, a creature into an object, or an object into a creature (the object must not be worn or carried by another creature). The transformation lasts for the duration of the spell or until the target drops to 0 hit points or dies. If you concentrate on this spell for its full duration, the transformation lasts until dispelled.

This spell has no effect on a shapechanger or on a creature with 0 hit points. An unwilling creature can make a Wisdom saving throw, and if successful, isn’t affected by this spell.

Creature into Creature. If you turn a creature into another kind of creature, the new form can be any kind you choose whose challenge rating is equal to or less than the target’s (or its level, if it doesn’t have a challenge rating). The target’s game statistics, including mental ability scores, are replaced by the statistics of the new form. It retains its personality.

The target assumes the hit points of its new form, and when it reverts to its normal form, the creature returns to the hit points it had before the transformation. If the transformation reverts as a result of the target dropping to 0 hit points, all excess damage carries over to its normal form. As long as the excess damage doesn’t reduce the target’s normal form to 0 hit points, it doesn’t fall unconscious.

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

The target’s equipment melds into its new form. The creature can’t activate, use, wield, or otherwise benefit from any of its equipment.

Creature into Object. If you turn a creature into an object, it transforms along with everything it is wearing and carrying into that new form. The creature’s statistics become those of the object, and it has no memory of the time it spent in this form after the spell ends and it returns to its normal form. Object into Creature. You can turn an object into any kind of creature, as long as the object’s size is no larger than the creature’s size and the creature’s challenge rating is 9 or lower. The creature is friendly to you and your companions. It acts on each of your turns. You decide what action it takes and how it moves. The GM has the creature’s statistics and resolves all of its actions and movement.

If the spell becomes permanent, you no longer control the creature. It may remain friendly to you, depending on how you treated it.