This modpack is a Pixelmon pack which can be played with a user-created or randomly generated map.
The Pixelmon mod is an implementation of Pokémon in Minecraft, so try to catch Pokémon, build your team, defeat trainer after trainer, etc.
You can get almost any Pokémon existing in the games and there are also almost all of the items from the Pokémon games implemented.
There are also a few information mods and a few pixelmon addons in this pack.
Have fun, if you give it a try.