Ryudamon is the Digimon partner of Rina Yamada. Ryudamon is a strange, quiet Digimon that gets irritated easily. If her tamer doubts herself, Ryudamon will turn into Fufumon. Ryudamon can fuse with Rina, or warp Digivolve to become Owryumon.
- Katana Attack: She jumps at the enemy, firing iron blade projectiles from her mouth.
- Helmet Reversal: She deflects his enemy's attack with her armored helmet using the power of her DigiCore.
The name "Ryudamon" refers to only the Rookie form of this Digimon. However, the Rookie form remains as the most common and preferred form, due to the amount of energy required to stay in a higher form.
Fufumon is the Fresh form of Ryudamon. Fufumon is a slime Digimon with a horn. She only appears when Rina doubts herself. Her only attack is Little Iron Spikes.
- Little Iron Spikes: Spits small iron spikes from its mouth at an approaching opponent.
Kyokyomon is the In-Training form of Ryudamon. Kyokyomon is a dragon Digimon. Her only attack is Metal Straw.
- Metal Straw: Stretches out and then fires an iron spike from its mouth.
Hisyarumon is Ryudamon's Ultimate form. Hisyarumon is a Chinese-dragon Digimon. Hisyarumon is a very strong Digimon with powerful attacks. After Ryudamon is done in this form, she is forced to return to Kyokyomon. Hisyarumon's strongest attack is Legendary Dragon Blade.
- Legendary Dragon Blade: Morphs himself into a giant blade and attacks.
- Every Direction Wheel: Wraps himself around the enemy while shooting energy blasts.
- Dragon Breath: Sends a breath of fire to destroy his enemies.
Owryumon is Ryudamon's Mega form. Like Hisyarumon, after this form, Ryudamon is forced to turn back to Kyokyomon. Owryumon's strongest attack is Immortal Dragon King Blade. Owryumon is known to represent Rina's kindness for others.
- Immortal Dragon King Blade: Fires an attack from the Gairyū Sadaijin and Gairyū Udaijin.
- Golden Armor: Rampages like the earthflow of a mighty river, tearing everything to pieces while charging the opponent.
- Dragon Summon: Summons a dragon demon possessed by the power of fire.
- Dragon's Darkness: Summons an eternal darkness, where several dragons will attack.
- Lethal hydro dragon (w/Plesiomon): Plesiomon creates a dragon out of water with the help of Owryumon