The Chaos Ambulation hack for Pokémon Emerald is a randomizer mod for Pokémon Emerald that makes it possible for all 386 Pokémon to follow the player around no matter where they go. As the player moves around, the first Pokémon in their party will accompany them and follow in their footsteps.
The sprites that were used for the overworld backgrounds in Pokémon HeartGold and Pokémon SoulSilver have been ported over to this game so that they can be used.
Although the Pokémon used in Pokémon Battles and Encounters are chosen at random from a pool of 386 Pokémon, each Pokémon is at the same level as it would be if it were collected in the wild. This applies to both of these types of encounters. (For example, a level 5 Ralts has the potential to evolve into any other Pokémon of that level, at which point it will be able to learn all of the moves associated with the new Pokémon it has become.)
