A series of four Bandai WonderSwan games released between 1999 and 2001 based on the Digimon franchise. The four games star Ryo Akiyama, a character who made a handful of cameo apperances in Digimon Adventure and Digimon Adventure 02 before becoming a Sixth Ranger in Digimon Tamers, and detail his ongoing conflict with the sinister Millenniumon. Their main draw is they are the hypothetical manual for exactly who the hell Ryo is, what he's doing in two different alternate continuities, and why he's seemingly out-of-place in the Tamers universe; they also link together all permutations of the franchise as a multiverse, which of course Ryo ends up saving.
Like the WonderSwan itself, all four games were a victim of No Export for You, and so while most people are aware they exist and they explain Ryo's backstory, non-Japanese fans who've played them or are aware of how exactly it all unfolded are few and far between.
The four games in the series:
- Digimon Adventure: Anode/Cathode Tamer (December 1999) (set around New Year's Eve 1999)
- Digimon Adventure 02: Tag Tamers (August 2000) (set shortly after the Our War Game Short Film; co-stars Ken Ichijouji)
- Digimon Adventure 02: D-1 Tamers (December 2000)
- Digimon Tamers: Brave Tamer (December 2001)
This series provides examples of:
- The Ace: The first three games all treat Taichi, The Leader of the original Digimon Adventure team, as the height of Tamer achievement. Indeed, Ryo's only called in when Taichi isn't able to help. Ryo finally surpasses him in the Tournament Arc of D1 Tamers, becoming the Ace himself.
- All There in the Manual: These games are the manual that shows who Ryo is, as he was a Hero of Another Story before his cameos in Adventures and Adventures 02, and before becoming the Sixth Ranger of Tamers.
- Arc Welding: The first three games bridge the gap between Adventure and 02.
- Character Development:
- Ryo grows from being scared and out of his depth in Anode Cathode Tamer to being a confident and capable Tamer in Tag Tamers. He then suffers a Heroic BSoD at the end of D1 Tamers before finally climbing out of it in Brave Tamer.
- Millenniummon goes from being dismissive of Ryo to mildly amused at his interference before finally going full-blown Yandere.
- Continuity Snarl: With Digimon Adventure, 02, and Tamers, which already have plenty of disagreements.
- Mons: Like other Digimon games, Digimon are gathered into teams and fight on Ryo's behalf.
- Not-So-Small Role: Ryo's friend Ken, his ally in Tag Tamers and a background presence in D1 Tamers. He is, of course, the same Ken as Digimon Adventure 02's, prior to becoming the Digimon Emperor.
- Villainous Crush: After his first defeat, Millenniumon gains a single-minded obsession for Ryo, lavishing him with Terms of Endangerment and subtext; everybody else (including Ken) he holds in absolute contempt. In Brave Tamer he goes so far as to claim to be Ryo's true partner, but he is also completely insane, so his word can be taken with a grain of salt.