Evolution from MetalGreymon. Requires massive Offense and Speed, and at least 40+ battles.
Pay attention to your Digimon's "Family." Staying within the same family (e.g., Nature Spirits or Virus Busters) makes hitting stat requirements easier as the stat gains carry over more effectively. digimon world re digitize evolution guide psp
Each Digimon has a "target weight." Feeding too much or too little can lock you out of certain forms. Evolution from MetalGreymon
Needs 2500+ HP and 300+ Offense/Defense/Speed. Battle count usually needs to be 30+. digimon world re digitize evolution guide psp
You can find or buy Digivolution Items (like the Grey Claws) that force an evolution regardless of stats. These are rare but vital for completing the Digivine encyclopedia.