A figurine of wondrous power is a statuette of a beast small enough to fit in a pocket. If you use an action to speak the command word and throw the figurine to a point on the ground within 60 feet of you, the figurine becomes a living creature. If the space where the creature would appear is occupied by other creatures or objects, or if there isn't enough space for the creature, the figurine doesn't become a creature.

The creature is friendly to you and your companions. It understands your languages and obeys your spoken commands. If you issue no commands, the creature defends itself but takes no other actions.

The creature exists for a duration specific to each figurine. At the end of the duration, the creature reverts to its figurine form. It reverts to a figurine early if it drops to 0 hit points or if you use an action to speak the command word again while touching it. When the creature becomes a figurine again, its property can't be used again until a certain amount of time has passed, as specified in the figurine's description.

Diamond Unicorn. This polished diamond unicorn can become a unicorn for up to 24 hours. The unicorn fights only to defend itself, and the only legendary action it can take is the Heal Self action. Once the figurine has been used, it can't be used again until 4 days have passed. 

If you have an evil alignment, the figurine has a 10 percent chance each time you use it to ignore your orders, including a command to revert to figurine form. If you mount the unicorn while it is ignoring your orders, you and the unicorn are instantly transported to a random location on the feywild, where the unicorn reverts to figurine form.

If the owner of the figurine dies while the unicorn is in unicorn form it casts revivify without material components on the owner as long as they are truly friends with the unicorn. If the unicorn sees someone else die, it may choose to cast revivify at the GM's discretion. The unicorn ignores any commands to cast revivify on evil creatures or creatures that have shown it cruelty. Once the unicorn casts revivify in this way, it can't again until it is next summoned. 

Notes: Summoning