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Phantasy Star Online is the most famous online RPG on the Dreamcast, but it wasn't the console's only stab at the genre.
Released in 2000, Hudson Soft's Rune Jade is an MMO where you select one of four character types and set off into a bunch of procedurally-generated dungeons. You can do this in either single-player or online mode, with the latter giving you the chance to team up with three other players.
As noted by Dreamcast Live, Rune Jade sadly didn't have much impact and was taken offline after just over a year. It never saw release outside of Japan, either.
The arrival of Phantasy Star Online a couple of months after it launched certainly won't have helped, but, as Dreamcasy Live explains, players of Rune Jade also had to shell out 300 Yen for a Play Pass in order to access it, whereas Phantasy Star Online was free.
All of that is moot now, as Rune Jade is back online thanks to the efforts of Flyinghead. You can download the patched file here. You'll naturally need all the gear to get your Dreamcast back online in 2026, as detailed here.