https://www.gamespot.com/articles/free-pokemon-legendary-for-ultra-sun-and-moon-reve/1100-6457884/

The Pokemon Company is continuing its year-long series of giveaways with another pair of free Legendaries for Pokemon Ultra Sun and Ultra Moon. This month, players will have a chance to get the Legendary dogs Entei and Raikou, but they'll only be available for a limited time.

As with most other Pokemon distributions, US players will be able to pick up a free download code for the Legendaries from a specific retailer. This time, the code will be available at Target stores from April 22-29. Those in Europe will be able to receive the Legendaries via an online Mystery Gift from April 4-25, while players in Canada can get a code in the Pokemon Trainer Club Newsletter.