Here's why:
* Game Design: The developers intentionally designed the game to encourage players to catch and discover Pokémon themselves.
* Cheating: Using AR codes to cheat is against the spirit of the game and can diminish the enjoyment of the experience.
* No Official Codes: There are no official or legitimate AR codes that allow you to instantly complete the Pokédex. Any such codes you find online are likely scams or outdated.
How to Fill Your Pokédex Legitimately:
1. Catch Pokémon: The most straightforward way is to explore different regions, encounter and catch various Pokémon, and evolve them.
2. Trade with Others: Trading with friends or other players allows you to acquire Pokémon you may not find in your region.
3. Use the GTS: The Global Trade System (GTS) lets you offer Pokémon and request specific Pokémon from others.
4. Breeding: Breeding allows you to obtain Pokémon with specific stats, abilities, and egg moves, which can be helpful in completing your Pokédex.
Remember, the best way to enjoy Pokémon HeartGold is by engaging with its mechanics and discovering Pokémon through exploration, trading, and battling.