Lance

Lance is a member of the Kanto Elite Four in Gen 1 (Pokemon Red) and Gen 3.5 (Randomized FireRed). He has been promoted to Champion of the Johto region in Gen 2 (Pokemon Crystal) and Gen 4.5 (Randomized HeartGold), as well as the champion of the Rijon region in Run 19 (Pokemon Prism). He is the father of Cyan.

History
In Twitch Plays Pokemon Red, Lance was the fourth and final member of the Elite Four to face Red and his team. His use of powerful Dragon-Type Pokémon like Dragonite has caused the first host of the Voices' party to be defeated twice. However, their first win against Lance became memorable, as it was obtained in a surprising way.

During the battle, five of Red's Pokémon were fainted, and only AATTVVV, a level 36 Venomoth, was left against Lance's level 62 Dragonite. Thinking the battle was lost once more, the Hivemind sent it out in order to retry the Pokémon League challenge as quickly as possible. However, this triggered an odd behavior in their favor from the A.I. It turned out the game was programmed so that Trainers would only choose, when possible, to use super-effective moves against the player's Pokémon. AATTVVV being a Bug/Poison-Type Pokémon, Lance's Dragonite repeatedly used the two Psychic-Type moves it knew, Barrier and Agility, which do not deal damage. This allowed the Venomoth to slowly bring down its Dragon-type foe, using a combination of Poison Powder and Leech Life, without losing any HP. Stunned by what just happened, the stream suddenly gained interest in AATTVVV, dubbing it 'The Dragonslayer'.

Lance returned in the following play-through, Twitch Plays Pokemon Crystal, as the final obstacle between AJ and the title of Champion of Johto. At that moment, the lore was already established as a quest of vengeance against Lord Helix, God of Anarchy, led by LazorGator, AJ's starter and strongest Pokémon. The battle opposing AJ and the Dragon-Type Champion saw the first recognized in-game appearance of a Fossil God other than the Omastar: Aerodactyl, a.k.a Lord Amber, God of Balance.

Many believe that LazorGator managed to withstand several deadly attacks (including paralysis inflicted by a Dragonite's Thunder Wave, Hyberbeams and Outrages from both Lance's Dragonites, as well as the Aerodactyl's own Hyberbeam), all of this to fulfil his ambition of killing all the gods, along with Helix. With an Icy Wind, the Feraligatr destroyed Lord Amber's mortal body.

After the randomization that occurred in TPP FireRed, Lance became a Poison-Type Trainer. This was interesting for the lore, because of the events of TPP Red. It was considered that Lance sought to master the type that had the best of him and his Dragon-Type Pokémon in the past.

In the next randomized play-through, however, Lance changed his type theme, switching to Electric. This change made him acquire two Raikous, in place of his two Dragonites in the original Pokémon HeartGold Version. However, where the Dragon/Flying Pokémon were a real threat to AJ's team in Crystal, Lance's legendary beasts did not pose problems to Aoooo's party, as it was mostly filled with Rock- and Ground-Type Pokémon. Plus, it took a few turns for the girl's starter, Trumprava, to end the fight, thanks to its repeated use of the move Magnitude.

Trivia

 * As in TPP FireRed, Lance's type theme is the same as Misty's, it has been theorized that Cerulean City's Gym Leader may have studied Poison-Types under the Elite Four member.
 * In both the original and anniversary runs of Red, Lance's team was composed of Pokémon described as dragons but not necessarily of the Dragon typing, including Gyarados (Water/Flying), Aerodactyl (Rock/Flying), Charizard (Fire/Flying) and Seadra (Water). As such, his team was mostly composed of Flying types rather than Dragon types due purely to a lack of Dragon type Pokémon (only the Dratini line in Generation 1).
 * He shares this trait with Agatha, whose team was mostly Poison rather than Ghost due to a lack of Ghost type Pokémon (only the Gastly line in Generation 1)