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The setting for the competition
The Lily of the Valley Conference (Japanese: スズラン大会 Suzuran Conference) is the Sinnoh League general championship competition.
The conference is held annually on Lily of the Valley Island. Competing Trainers are housed in hotels in small villages similar to previous leagues. The conference took place from An Old Family Blend! to The Semi-Final Frontier! in the anime.
The conference was the first conference to feature a direct tie between beating the conference and later fighting the Elite Four and Champion to become a Pokémon Master, which was stated by Lucian in The Elite Meet and Greet!. Although Elite Four members have appeared in prior regions in the anime, there was no explicitly stated tie between beating the regional conferences and challenging the Elite Four until then.
Although they aren't shown in full detail, the opening ceremonies include a fireworks show and the lighting of the league torch.
The scoreboard for the Full Battles
Although not shown, it is assumed that there are some sort of screening rounds as there were many Trainers seen registering for the competition in An Old Family Blend!, but not seen in the actual battle round match-ups shown later in the episode, an example being Jeffrey.
The Top 64 Trainers preceded onto the actual tournament. The first three rounds feature three-on-three matches. The first two rounds are held in the three small arenas of the venue, while the Top 16 matches are held in the main arena. The battles take place on either a Rock, Grass, Water, or Ice field. When all three Pokémon are unable to battle, the Trainer is knocked out of the tournament.
After shuffling the match-ups, the Top 8 Trainers then compete in the center arena in a series of Full Battles. When either Trainer has lost their six Pokémon, they are knocked out of the tournament. Beginning in this league, breaks were not given out to any of the Trainers whose three Pokémon were knocked out.
Although they aren't shown in full detail, the closing ceremonies include a fireworks show, the league torch being extinguished, and Mr. Goodshow and Cynthia presenting the winner with a trophy.
Tobias, the winner, with the Lily of the Valley Championship Trophy
Trainers here participated in the conference before the conference Ash entered.