Subtitle: Guardian Enemy Monster (油断大敵怪獣 Yudantaiteki Kaijū)
Greyjhom is named after the Grey Zone, a form of mental disorder.
Greyjhom suddenly appeared underneath a bridge, attracting the attention of onlookers. The Kaiju Eugenicists were at the scene and Juuga used his Instance Domination on it, putting the monster under his control and making it grow to giant size. News was quickly spread through the Internet, catching the attention of the Dynazenon pilots, sans Yomogi Asanaka who skipped his training. Yomogi was picked up in Dynawing and they prepared to fight as Dynazenon, but the monster's warping ability put them at a disadvantage. Dynazenon split into its components but their teamwork was off due to Yomogi's lack of training in Dynasoldier, though they manage to defeat Greyjhom by combining into Dynasoldier Wing Combine to hold its wings down mid-air then having Dynadiver blow it apart with missiles.
- Designer: Yasushi Torisawa
- Height: 71 m
- Weight: 60,000 t
- Date of Birth: 28 May, 2020
- Powers and Weapons
- Warp (ワープ Wāpu): Greyjhom can teleport after opening up its wings. However, it is unable to use this ability if the wings are held in place, or destroyed.
- Blade Arms: Greyjhom's arms end in bladed appendages that it uses to attack with.
- Beams: Greyjhom fires destructive beams from its chest and back.