The Digital World, a cyberspace where creatures called Digimon roam. Many humans have encountered different Digimon over the years. Like their predecessors, the humans of this generation, Digimon Frontier, are also DigiDestined but in a way different: They are the Digimon. They have the reminiscent spirits of The Legendary Warriors. AncientGreymon, Spirit of Fire. AncientGarurumon, Spirit of Light. AncientBeetlemon, Spirit of Thunder. AncientKazemon, Spirit of Wind. AncientMegatheriumon, Spirit of Ice. AncientMermaimon, Spirit of Water. AncientSphinxmon, Spirit of Darkness. AncientTroiamon, Spirit of Wood. AncientVolcamon, Spirit of Earth. AncientWisemon, Spirit of Steel. Soon after, two more DigiDestined were revealed with Spirits. Ashley Orohugh, she possesses the Spirit of the Crescent from AncientDianamon who suffered the some fate as the others Legendary Warriors. And Daren Huoichi, he possesses the Spirit of Earth from AncientBouldozermon. Daren's Spirit is easily questionable. Grumblemon is suppose to be the Spirits of Earth from AncientVolcamon.
The explanation: AncientVolcamon and AncientBouldozermon were one is the same until he became more powerful when battling Lucemon. Lucemon divided AncientVolcamon into a separate Legendary Warrior, AncientBouldozermon, the 12th Legendary Warrior. Thus, creating two different Spirits of Earth pairs. Grumblemon/Gigasmon and Bouldozermon/DexiDigmon. 8 of the 12 Warriors are embroidered to humans making them DigiDestined. The other 4 become figures that threaten the DigiDestined. Ranamon, Grumblemon, Mercurymon, Arbormon are the these figures. Ranamon is the Human Spirit of Water and can become Calmaramon, the Beast Spirit. Mercurymon is the Human Spirit of Steel and can become Sakkakumon, the Beast Spirit. Arbormon is the Human Spirit of Wood and can become Petaldramon, the Beast Spirit. Grumblemon is AncientVolcamon's Human Spirit of Earth and can become Gigasmon, the Beast Spirit. He sometimes has a grudge against Daren and by taking his AncientBouldozermon's Spirit of Earth's fractal code, he'll become more powerful. But ultimately, Daren digitizes his fractal code, completing the Spirit of Earths an ability to become TierraDigmon.
Speaking of the DigiDestined. There eight in total. Takuya Kanbara is the leader of the group with the Spirit of Fire. Human Spirit is Agunimon and Beast Spirit is BurningGreymon. Fusion form is Aldamon and Unified form is EmperorGreymon. Koji Minamoto, he was quiet and reserved and the "lone wolf" with the Spirit of Light. Human Spirit is Lobomon and Beast Spirit is KendoGarurumon. Fusion form is Beowulfmon and Unified form is MagnaGarurumon (A/N: Takuya and Koji have Aldamon and Beowulfmon). J.P. Shibayama, used to be the oldest of the group until Daren and Ashley joined matching the ages of 12 with the Spirit of Thunder. Human Spirit is Beetlemon and Beast Spirit is MetalKabuterimon. Zoe Orimoto, used to be the only female of the group until Ashley joined giving her some other feminine figure to talk to and is very independent with the Spirit of Wind. Human Spirit is Kazemon and Beast Spirit is Zephyrmon. Tommy Himi, the youngest of the group with the Spirit of Ice. Human Spirit is Kumamon and Beast Spirit is Korikakumon. Koichi Kimura, Koji's twin brother who separated when their parents divorced. Originally lost memory and became Duskmon/Velgemon, an enemy but purified afterwards. With the Spirit of Darkness, the Human Spirit is Loewemon and Beast Spirit is JagerLoewemon.
Daren Huoichi, a protective and caring person with AncientBouldozermon's Spirit of Earth. Human Spirit is Bouldozermon and Beast Spirit is DexiDigmon. Like Koji, Takuya, and Ashley, he can become a Fusion Form (Terramon) and Unified Form (TierraDigmon, but after completion of Spirit of Earth). He has a bit of a crush of Zoe (she does too). Sometimes Ashley and Daren bicker over decisions like Takuya and Zoe's disagreements. Lastly, Daren can speak Spanish (same situation that enabled Zoe to speak Italian). Ashley Orohugh, a reliable and trustful friend (but acts a bit like Rika from Digimon Tamers a bit) with the Spirits of the Crescent of AncientDianamon. Human Spirit is Crescentmon and Beast Spirit is ShadowLunarmon. Like Koji, Takuya, and Daren, she can become a Fusion Form (Darusumon) and Unified Form (PretDianamon). Ashley and Zoe are considered best friends being the only two feminine characters of the group. Sometimes Ashley and Daren bicker over decisions like Takuya and Zoe's disagreements. Bokomon and Neemon are accompanying Digimon. Bokomon give the knowledge of the Legendary Warriors, on other Digimon, etc. Neemon is just there for the ride.