Pokemon XD: Gale of Darkness is a fun Pokemon game in which you get to go on another journey in the Orre region, and stop Cipher once again from making Shadow Pokemon. To complete the game, you must not only complete the story itself, but capture and purify all 83 shadow pokemon, including XD001 (Shadow Lugia). There are reasons why this game became popular.

1. Shadow Pokemon returned.
Shadow pokemon was the thing that made Pokemon Colosseum so popular! It introduced a new way of catching pokemon. You use a snag machine to snag shadow pokemon from other trainers, so you can purify them.

2. An old villian returned.
From Pokemon Colosseum, Miror B. is back with his Lombres and Ludicolos, along with a few shadow pokemon. Miror B. was disband from Cipher after the first shadow pokemon plan was ruined, along with the other previous Cipher admins. Cipher went down in ruins, but returned in this game, but Miror B. is the only previous admin from Cipher, and he is considered a wonderer in this game.

3. New legendary shadow pokemon.
Instead of having shadow Entei, Raikou, and Suicune, in this game we have shadow Lugia, Zapdos, Articuno, and Moltres. They are harder to catch because they are all with one trainer. The final boss, Master Greevil.

4. Cipher returns.
Cipher comes back again, trying to make shadow pokemon, and the admins are different. The leader of Cipher is also different. You must stop Cipher again, but with only one Eeveelution, and you get to choose it.