Ryudamon

A Digimon wearing a helmet and other armor-like features. He has a kind heart, and even though he evolved into the ferocious Gyukimon, he still wished to return to his original form and came to Hiro, relying on Hokuto's words. He succeeded in returning from Gyukimon to Ryudamon through the efforts of Hiro and Gammamon.

(Source: Official website, translated)