Without having tried it, I think it could work very well. Demonic Disaster helps you perform an OTK after attacking with Mastemon. The steps would be:
1: When you perform DNA, both you and your opponent are left with three lives.
2: Attack using alliance, leaving your opponent with one life.
3: Use Demonic Disaster to unsuspend Mastemon.
4: Use the effect of Terriermon/Palmon to put Mastemon underneath and digivolve into Alphamon to end the game by attacking twice.
