Riolu

Riolu is a playable Pokemon in Pokemon Simulator. It is common. It is for free.

Family members
After the player has gained exactly 1,000 points at anytime, they can unlock family members. This makes it hunt cowardly Pokemon better.

Evolution
To evolve Riolu into Lucario, the player needs to keep hunting some Pokemon. The player can Mega Evolve Lucario if they have a Lucarionite. The Lucarionite can randomly be found anywhere in the forest.

Trivia

 * Riolu is the first playable Pokemon in this game.
 * Riolu is the first playable Pokemon to be a carnivore.