[RPG] the lowest CR creature that has Legendary Actions


What is the lowest CR creature that has Legendary Actions?

I'm open to answers referencing creatures from any officially published WotC resources, including named NPCs in published adventures or DDAL (Adventurers League).

Best Answer

We have a winner at CR 3

As of now, according to a search on DnD Beyond, there are two creatures who win at CR 3:

There is the Fleecemane Lion from the Mythic Odysseys of Theros. There is also Bol'bara who is from the Explorer's Guide to Wildmount. There are some specific requirements for them to have legendary actions which are mentioned in mdrichey's answer. Thanks to mdrichey for finding this option in the first place.

Below is my previous answer prior to the release of Wildmount:

There are two creatures tied at CR 4 that have legendary actions:

The Yestabrod from Out of the Abyss and the Thessalhydra from Hunt for the Thessalhydra.

There is also the honorable mentions of the Merrenoloth from Mordenkainen's Tome of Foes; a CR 3 character with lair and regional actions though no legendary actions.

There is also, as mdrichey points out, the Unicorn at CR 5 from the Monster Manual, who has legendary actions, is not from a specific module, and is not a specific (single) character/creature. Thanks, again, to mdrichey for bringing up the Unicorn as an option/example.