Greetings,
Here are the details for the Gotta Catch 'Em All! event.

Poké-Flaris

Flarine has received a big makeover, and it now looks like your usual Pokémon City! On top of that, the entire continent of Flaris is fitting the theme.

Wild Pokémons

Pokémon from Generation 1 Pokémon games are now roaming around Madrigal.
Players are able to defeat them in order to earn Pokédollars depending on the Pokémon's rarity and strength.

A small percentage of the Pokémons roaming around can be Shiny! Shiny Pokémons have the same stats and catch rate as their normal version, they, however, have a different colour scheme, and cannot flee from players. Upon encountering a Shiny Pokémon, stars will appear around them, and a sound will play, in order to make them easier to notice. Don't miss them!

Catching Pokémon

Players are able to catch wild Pokémons by using any kind of Poké Ball.
To do so, they can equip Poké Balls as their weapon, and attack the Pokémon with them.
This will cause the character to throw the Poké Ball at the Pokémon, and attempt to catch it.
Each Pokémon has its own catch rate, which can be increased by lowering the Pokémon's HP before attempting a catch, as well as using higher quality Poké Balls, such as Great Balls or Ultra Balls. Additionally, using the item White Flute grants a 30% Catch Rate buff for 1 Hour.

If the catch fails, the Pokémon will continue doing what they were up to, however, there is a chance the Pokémon may flee upon failing a catch.
If the catch succeeds, the player will receive a Pick-Up Pet version of the Pokémon, as well as Pokédollars! Please note, however, that the caught Pokémon will be Untamed, which means they cannot be summoned. See the "Raising Pokémon" section to read more about Untamed Pokémons.

Raising Pokémon

So you've caught your first Untamed Pokémon, great job! Now what?

Pokémons that have just been caught are not tame yet. In order to tame a Pokémon, players will need to feed them the appropriate Species Candy by double-clicking the candy in their inventory and clicking the Untamed Pokémon. By doing so, the Pokémon will eat the candy, which will give them a random chance to acquire your trust and become tamed.
Once a Pokémon has been tamed, it can be summoned and their level can be increased.

In order to Raise Pokémons, players will need to use the Pokémon Menu, which is accessible by talking to the Pet Tamer in Flarine.

The Level of a Pokémon can be increased by using a Rare Candy or a Species Candy. Certain Pokémons may evolve upon reaching a required level, so keep your eyes open for that!

Leveling a Pokémon is however not the only way to evolve a Pokémon. A select few Pokémons will not evolve only by having their level raised. They also require a peculiar stone to be used in order for them to evolve. For example, Vulpix may not evolve into Ninetales until the player uses a Fire Stone on them (Required Level: 24).

Additionally, by using the Pokémon Menu, it is possible to release a Pokémon, in order to obtain Species Candy for their species. The amount of Candies received will vary depending on the Pokémon, their evolution, and their Level.

Legendary Pokémon

Much like Ghost's well known Rangdas, Pokémon World Bosses also exist, under the form of Legendary Pokémon.
Players may fight them as a group in order to obtain rewards upon defeating them. The rewards include Species Candy of the World Boss.

By gathering enough Species Candies of a Legendary Pokémon, players may craft them into an item allowing them to summon said Pokémon. This allows the player to attempt to catch the Legendary Pokémon!

Safari Zone

It is possible for players to enter the Safari Zone a limited amount of times per day.
Within this time-gated area are special Pokémon that cannot be found anywhere else and cannot be damaged by the player.
These Pokémon can be caught by using any kind of Poké Ball. They have a higher catch rate, but they also have a higher flee rate, so make sure to pick the right Poké Ball for the catch!
The Instance can be found at the collector field in Flaris.

Pokédollar Store

Players may spend their Pokédollars to obtain various items, such as several types of Poké Balls, or costumes, at the Pokédollar Store. The NPC holding this store is Mysterious Boy, located in Northern Flaris.