Imperialdramon Fighter Mode

Imperialdramon Fighter Mode is from the Digimon 02 series. Once his full potential was realised, Imperialdramon Mode Changed to Fighter Mode. Taking on a human shape has enabled more precise control over his immense power.

Digimon Adventure 02
He first appeared in Episode 43 of the Digimon Zero Two Series. When SkullSatamon froze Imperialdramon, the Digimon of the older DigiDestined De-Digivolved from their Ultimate forms because they weren't used to being in the Real World for so long. They, along with the Digimon of the younger DigiDestined, gave their remaining power they received from Azulongmon, allowing Imperialdramon to Mode Change to Imperialdramon Fighter Mode.

Diaboromon Strikes Back
In Movie 4, after Omnimon lost to Armageddemon, Davis and Ken were able to locate Veemon and Wormmon (they were separated after the Kuramon began to emerge in the Real World). They Digivolved to Imperialdramon Fighter Mode and tried to use their Giga Crusher (a different version of what was used in the TV Series), however, it wasn't strong enough and Imperialdramon was injured in Armageddemon's counterattack. In the end, Omnimon gave his remaining energy to Imperialdramon Fighter Mode by having its main body become the Omni Sword (Omega Blade) which transformed Imperialdramon Fighter Mode into Imperialdramon Paladin Mode.

V-Tamer
The evil Metamormon became Imperialdramon Fighter Mode and attacked Taichi Yagami, Zeromaru, and Takuya Kanbara. Metamormon became Imperialdramon Fighter Mode again and injured BurningGreymon.